Leptin Concentrations In Women Research Articles

Breastfeeding duration modifies the association between maternal weight status and offspring dietary palmitate oxidation

Offspring of obese rodents develop a metabolic phenotype that favors fat deposition. Data regarding the impact of maternal obesity programing of offspring fuel usage in humans is scarce. The objective of this study was to explore the association between maternal weight status and dietary palmitate oxidation (DPO) in 2-y-old offspring, taking into consideration potential confounders and modifiers. Women (n=56) were enrolled by the first trimester of gestation. Maternal physical activity (PA; measured with accelerometers) at enrollment and gestational weight gain (GWG) were measured. Offspring sex, race, and breastfeeding (BF) duration were self-reported. Human milk (HM) composition was determined at 6mo postpartum. At age 2 y, dietary quality [healthy eating index (HEI)] and parental feeding practices [Child Feeding Questionnaire (CFQ)] were assessed. DPO in 2-y-olds (2-yo-DPO) was measured using deuterated palmitic acid. Generalized linear regression analysis was used to model the associations of 2-yo-DPO with maternal weight status [normal weight (NW), BMI <25 (in kg/m2) compared with excessive weight (EW), BMI ≥25]. DPO was higher in offspring of women with EW compared with NW (2.1±1.2%/h compared with 1.4±0.7%/h, P=0.03). Maternal weight status interacted with BF duration in association with 2-yo-DPO (log ß: 0.05, P=0.04). Specifically, 2-yo-DPO was higher in the EW compared with NW group if BF duration was ≥9mo. HM insulin (log ß: 0.35, P=0.002) and HM leptin (log ß: 0.81, P=0.001) concentrations directly associated with 2-yo-DPO. PA (log ß: 0.06, P=0.013), parental feeding restriction (log ß: 0.05, P<0.0001), and male sex (log ß: 0.54, P<0.001) were positively associated with 2-yo-DPO. HEI was negatively associated with 2-yo-DPO (log ß:-0.03, P<0.0001). Higher 2-yo-DPO in offspring of women with EW compared with NW were driven by BF duration. Higher HM insulin and leptin concentrations in women with EW may explain these finding. More studies are needed to confirm these results. This trial was registered at clinicaltrials.gov as NCT03281850.

FRIED FOOD AND POSSIBLE HEALTH HAZARDS

FRIED FOOD AND POSSIBLE HEALTH HAZARDS

Sex differences in body fat distribution are related to sex differences in serum leptin and adiponectin

It is debated whether sex differences in adiponectin and leptin are due to sex differences in body fat distribution. In this cross-sectional analysis of the Netherlands Epidemiology of Obesity study, associations of measures of body fat and sex with serum adiponectin and leptin concentrations were examined using linear regression analysis (n = 6494, VAT: n = 2516). Sex differences were additionally adjusted for the measure of body fat that was most strongly associated with adiponectin or leptin concentrations. Median adiponectin concentrations in women and men were 10.5 mg/L (IQR, interquartile range: 7.7–13.9) and 6.1 mg/L (IQR: 4.5–8.2), mean difference 4.6 mg/L (95% CI: 4.3, 4.9). Median leptin concentrations in women and men were 19.2 μg/L (IQR: 11.5–30.0) and 7.1 μg/L (IQR: 4.6–11.1), mean difference 15.1 μg/L (95% CI: 14.4, 15.8). VAT was most strongly associated with adiponectin, total body fat percentage was most strongly associated with leptin. After adjustment for VAT, women had 3.8 mg/L (95% CI: 3.3, 4.3) higher adiponectin than men. After adjustment for total body fat percentage, leptin concentrations in women were 0.4 μg/L lower than in men (95% CI: −1.2, 2.0). One genetic variant (rs4731420) was associated with extreme leptin concentrations (>100 μg/L) in women: odds ratio 2.8 (95% CI: 1.7, 4.6). Total body fat percentage was strongly associated with leptin concentrations. Higher leptin concentrations in women than in men were completely explained by differences in total body fat percentage. Visceral fat was associated with adiponectin concentrations, and did not completely explain higher adiponectin concentrations in women than in men.

Serum leptin concentration in women of reproductive age with euthyroid autoimmune thyroiditis

Introduction: Autoimmune thyroid disease (AITD) with elevated anti-thyroid peroxidase antibody (aTPO) levels appears in 12–25% of all women, apart from thyroid dysfunction. High titers of aTPO are more common in women with polycystic ovary syndrome and endometriosis. Elevated aTPO has been associated with infertility and poorer quality of life among euthyroid women, and may be related to other factors.Objectives: The aim of the study was to measure differences in serum leptin concentration between AITD+ and AITD− patients.Setting, patients and main outcome measures: The sample was comprised of 74 women who were hospitalized in the Department of Gynecological Endocrinology, Medical University of Warsaw. Data collected included age, body mass index (BMI), and serum aTPO, serum thyroid stimulating hormone (TSH), serum fT4, serum follitropin (FSH), serum estradiol and serum leptin. AITD positive status was defined as serum aTPO greater than 5.6 mIU/ml.Results: Serum leptin concentrations were significantly higher in AITD+ patients compared to AITD− patients (17.13 ng/ml [SD 7.66] versus 12.78 ng/ml [SD 7.28]; p < 0.05). No differences by AITD status were found in age, BMI, TSH, FSH, estradiol and fT4.Conclusions: Serum leptin concentrations were higher in patients with AITD than in patients without AITD.

A Comparative Study of Serum and Follicular Fluid Leptin Concentrations among Explained Infertile, Unexplained Infertile and Fertile Women.

The relationship between metabolism and reproduction has been always considered as an important topic in female endocrinology. It seems that leptin is one of the involved factors in infertility. Leptin, in addition to regulating body weight plays an important role in regulation of endocrine, reproductive and immune systems. The aim of this stduy is to compare serum and follicular fluid leptin concentrations in order to find the role of leptin level in infertility. This case-control study was performed from September 2010 to March 2013. A total of 90 women referred to the Infertility Center of Afzalipour Hos- pital, Kerman, Iran, and divided into three equal groups (n=30/per group) of explained infertile (including 4 subgroups), unexplained infertile and normal fertile (control group). The three groups were matched in regard to demographic features [age: 20-40 years and body mass index (BMI): 20-25]. In order to determine leptin level, blood sample and fol- licular fluid were taken one hour prior and at the time of follicular puncture, respectively. Serum and follicular fluid leptin levels were measured using enzyme-linked immune sorbent assay (ELISA). Data were analyzed using descriptive-analytic tests, like Mann- Whitney and Kruskal Wallis tests, through Statistical Package for the Social Sciences (SPSS) version 16. In explained infertile and fertile groups, as opposed to unexplained infertile group, mean leptin level was lower in follicular fluid than in serum. Mean follicular fluid leptin concentration in women with unexplained infertility was higher com- pared to the other two groups. Women with unexplained infertility had lower level of serum leptin in comparison to the other two groups. Follicular fluid leptin level in all subgroups of explained infertile group was lower as compared to unexplained and fertile women. The results suggested that high leptin level of follicular fluid is one of the main factors involved in infertility.

Weight status and dietary intake determine serum leptin concentrations in pregnant and lactating women and their infants

Leptin regulates energy homeostasis and immune and metabolic functions. Highly elevated leptin concentrations during pregnancy may be associated with aberrations in maternal metabolism and long-term health consequences both in women and children. The objective of the present study was to evaluate whether dietary counselling, probiotic supplementation, maternal characteristics or dietary intake during pregnancy has an impact on serum leptin concentrations in women, cord blood or in children. A total of 256 pregnant women were randomised to a control group (n 85) or to receive dietary counselling with probiotics (n 85) or placebo (n 86). Dietary counselling aimed at affecting the type of fat used and to increase the amount of fibre in the women's diet. Women's dietary intake and serum leptin concentrations were analysed at the first and third trimesters of pregnancy and at 1 month postpartum. Furthermore, leptin concentrations were measured from the cord blood and from children's serum at 1 and 6 months of age. Weight status and dietary composition were the key determinants of leptin concentrations. Specifically, high dietary fibre and low SFA intakes were related to low serum leptin concentrations in women. Female sex and birth weight were associated with higher infant leptin, whereas cord blood leptin was additionally affected by maternal leptin concentration and protein intake. Probiotics or dietary counselling did not affect leptin concentrations. Weight control to recommended levels and modification of diet towards higher fibre and lower SFA intakes during pregnancy may through leptin concentrations provide health benefits to both women and children.

Depot-specific and sex-specific secretion of leptin and interleukin 6: higher leptin release in women and lower interleukin-6 release from femoral adipose tissue in vivo

BackgroundThe female fat distribution pattern of gluteofemoral fat mass accumulation is associated with protection from cardiovascular disease and diabetes. Furthermore, women are known to have higher systemic leptin concentrations than men. Differential adipokine secretion from subcutaneous adipose tissue depots may be responsible for these differences. We aimed to study the physiological release of leptin and interleukin (IL) 6, a pro-inflammatory adipokine, from abdominal and femoral adipose tissue in vivo. MethodsDepot-specific leptin and IL-6 release were measured in 42 healthy volunteers (23 men and 19 women), matched for age and body-mass index (mean 25·4 kg/m2). Measurements were carried out after an overnight fast. Leptin and IL-6 release were studied with the arteriovenous difference technique across abdominal and femoral adipose tissue. FindingsLeptin release showed a strong sex dichotomy with 3·5-fold higher systemic plasma concentrations (p<0·001) and a 3-fold higher leptin release rate per unit fat mass across abdominal and femoral adipose tissue in women than in men (p<0·05). In both men and women, abdominal and femoral leptin release were positively correlated with each other (r=0·54, p<0·001), and negatively correlated with waist-to-hip ratio (p<0·001, controlled for sex). Abdominal IL-6 release was higher than femoral IL-6 release (p=0·001), which was a consistent finding in both men and women. InterpretationAdipose tissue is characterised by differential adipokine secretion between sexes and subcutaneous fat depots. The widely observed higher systemic leptin concentration in women is a result of a high leptin production rate and large gluteofemoral fat mass compared with men. Femoral adipose tissue is characterised by a lower IL-6 release rate, which may suggest that gluteofemoral fat is resistant to low-grade inflammation. FundingHigher Education Funding Council for England.

Comparative effects of metformin and pioglitazone on omentin and leptin concentrations in patients with newly diagnosed diabetes: A randomized clinical trial

AimsTo assess the effects of two commonly used oral hypoglycemic medications metformin and pioglitazone on serum concentrations of omentin and leptin in patients with newly diagnosed type 2 diabetes. MethodsIn a clinical trial setting (NCT01593371), patients were randomly allocated to either metformin 1000mg daily (n=41), or pioglitazone 30mg daily (n=50). Serum concentrations of omentin and leptin were measured at baseline and after 12weeks. Patients' weight, waist circumference, blood pressure, fasting plasma glucose, fasting insulin, HbA1c, highly sensitive C-reactive protein, and serum lipids were also measured at the two visits. ResultsBaseline concentrations of omentin and leptin were not different between the two arms of the trial. After three months, metformin decreased both omentin and leptin concentrations in women, and leptin concentrations only in men. On the other hand, pioglitazone reduced both adipokines only in women, but not men. Univariate and multivariate ANCOVA models revealed that both interventions are equally effective in reducing omentin concentration (p=0.497 for women and 0.344 for men in multivariate models controlling for the effects of confounding variables). Similarly, neither medication was more effective in reducing leptin concentrations after three months (p=0.822 for women and 0.441 for men in multivariate models). ConclusionsMetformin and pioglitazone at pharmacologic doses are equally effective in alteration of serum omentin and leptin concentrations in patients with diabetes, albeit sex differences in response to medications exist. Implication of these findings on long term management and complication prevention of diabetes needs to be elucidated.

Zinc, vitamin A, and vitamin C status are associated with leptin concentrations and obesity in Mexican women: results from a cross-sectional study

BackgroundThe prevalence of obesity among Mexican women is high and it could be related to micronutrient status. We evaluated in a cross-sectional study the associations of zinc and vitamins A, C and E concentrations with BMI, central adiposity, body fat and leptin concentration.MethodsWomen aged 37 ± 7.5 years (n = 580) from 6 rural communities in Mexico were evaluated. Anthropometric measurements included weight, height, waist and hip circumference. A fasting blood sample was taken for the analysis of glucose, lipid profile, leptin, zinc, and vitamins A, C and E. Body composition was determined by DEXA (Hologic Mod Explorer).ResultsThe prevalence of overweight and obesity was 36% (BMI > 25 Kg/m2) and 44% (BMI > 30 Kg/m2), respectively. Prevalence of zinc and vitamins C and E deficiencies were similar in obese, overweight and normal weight women. No vitamin A deficiency was found. Vitamin C was negatively associated with BMI, waist-to-height ratio, and leptin concentrations (p < 0.05). Vitamin A was positively associated with leptin (p < 0.05). When stratifying by BMI, % body fat and waist circumference, high leptin concentrations were associated with lower zinc and lower vitamin C concentrations in women with obesity (p < 0.05) and higher vitamin A concentrations in women without obesity (p < 0.01). Vitamin E status was not associated with any markers of obesity.ConclusionZinc and vitamins A and C are associated with obesity, adiposity and leptin concentration in women from rural Mexico, and may play an important role in fat deposition. The causality of these associations needs to be confirmed.

Leptin and interferon-gamma as possible predictors of cesarean section among women with hypertensive disorders of pregnancy

SummaryBackgroundThis study was designed to evaluate maternal levels of leptin and interferon-gamma (IFN-gamma) in pregnancy complicated with hypertension and to assess the role of cytokines in predicting the risk of cesarean section.Material/MethodsThis was a cohort study with a prospective follow-up. After proportional sampling procedure, the study included the follow-up of 40 women with hypertensive disorders of pregnancy (pregnancy-induced hypertension [PIH] or preeclampsia [PE]) and 40 uncomplicated pregnancies. Women were followed from the time of admission to the delivery. Levels of leptin and interferon-gamma were measured in serum samples from all women. A p-value <0.05 was considered as significant.ResultsSignificant increase in IFN-gamma and leptin concentration in women with pre-eclampsia was observed. We found a significant 1.4-fold increase in the risk of birth by cesarean section associated with the increase of the IFN-gamma concentration by 0.1 pg/ml and almost 3-fold increase in the risk associated with the increase of the leptin concentration.ConclusionsIFN-γ and leptin might be risk markers of cesarean section in hypertension disorders of pregnancy, but further studies supporting this evidence are needed.

Serum Leptin Concentration Positively Correlates with Body Weight and Total Fat Mass in Postmenopausal Japanese Women with Osteoarthritis of the Knee

The objective of the present study was to identify factors correlated with the serum leptin concentration in women with knee OA. Fifty postmenopausal Japanese women with knee OA (age: 50–88 years) were recruited in our outpatient clinic. Plain radiographs of the knee were taken, and urine and blood samples were collected. Dual-energy X-ray absorptiometry (DXA) scanning was performed for the whole body and lumbar spine, and factors correlated with the serum leptin concentration were identified. A simple linear regression analysis showed that body weight, body mass index, whole-body bone mineral density (BMD), total fat mass, and total fat percentage, but not age, height, lumbar spine BMD, lean body mass, serum and urinary bone turnover markers, or the radiographic grade of knee OA, were significantly correlated with the serum leptin concentration. A multiple regression analysis showed that among these factors, only body weight and total fat mass exhibited a significant positive correlation with the serum leptin concentration. These results suggest that the serum leptin concentration might be related to increases in body weight and total fat mass, but not to BMD or bone turnover markers, in postmenopausal women with OA.

Gender differences in body composition, inflammatory markers and risk of metabolic abnormalities in Arabs

Abstract Background: Metabolic syndrome may be a result of both increased and/or inappropriate fat accumulation. As a consequence of the obesity epidemic, which has particularly manifested amongst the populations of the Arabian Gulf, associated with increases in type 2 diabetes mellitus and cardiovascular diseases, metabolic syndrome is becoming an increasing problem. Recent studies from the Gulf region have highlighted that women are more at risk than men. The effect of gender on fat accumulation and distribution, as well as its secretory function, are yet to be studied. Purpose: The aim of our study was to investigate gender differences in body composition, aerobic fitness, adipokines and inflammatory markers in a cohort of healthy Qatari adults. Methods: This was a prospective case-control study of healthy Qatari adults (18-50 years of age), comprised of 29 women matched with 29 men for age and body mass index. Detailed investigations included body composition by anthropometric measurements, DXA and CT scans to assess total and regional fat distribution. Subjects were also evaluated for their aerobic fitness and indices of muscular strength. Hematological investigations included fasting glucose, insulin, HOMA-IR, lipid profile analysis, adipokines (s-adiponectin, leptin) and inflammatory markers (IL-6, MCP-1, CRP, S.RANTES). Results: Waist circumference in males (95.4±17.4 cm) and females (90.1±11.3 cm) was comparable (p=0.192). CT scan results revealed that women accumulate comparatively more fat in the total abdominal (p=0.036), and abdominal sub cutaneous (p=0.066) and total thigh (p<0.001) regions. No differences were detected in HOMA-IR, and despite very high adiposity, the lipid profile was favorable in females (TG=0.8±0.4 vs. 1.2±0.5 mmol/L and LDL=2.8±0.7 vs. 3.2±0.9 mmol/L). Poor aerobic fitness (<50th percentile) was observed in both groups 96% in women compared to 70% in men (p<0.001). S-adiponectin and leptin levels were significantly elevated in females, whereas CRP, IL-6, MCP-1 or S.RANTES were no different. Conclusion: Elevated leptin concentration in women was attributed to a high percentage of central obesity in the test subjects. The presence of higher levels of s.-adiponectin led to a favorable lipid profile in women. In contrast, deleterious gender differences in aerobic fitness within this population is of critical relevance and must be further investigated.

Anthropometric and Leptin Changes in Women Following Different Dietary Approaches to Weight Loss

Leptin may favorably respond to fat mass (FM) losses induced by a low-carbohydrate (LC) diet, although this is unclear. We examined serum leptin concentrations in women in midlife undergoing different dietary approaches to body weight (BW) loss. Women followed either a LC, high-protein (LCHP; n = 13) or high-carbohydrate, low-fat (HCLF; n = 12) diet for 12 weeks. Changes in anthropometric and soft-tissue mass measurements and leptin concentrations were assessed. Women in both diet groups had reductions in BW, BMI, fat-free soft-tissue mass, FM, body fat percentage, and central abdominal fat (CAF) (P < 0.001 for all variables) over the 12-week intervention. These changes were not significantly different between diet groups. Serum leptin concentrations decreased by 41.8% (P < 0.001) in the LCHP group and by 44.3% (P < 0.001) in the HCLF group from baseline to week 12, with no significant difference between groups. The association of CAF (r = 0.73) and FM (r = 0.83) change with leptin change was strong in the HCLF group. Leptin change did not relate to change in any variable in the LCHP group. Both LCHP and HCLF diets favorably lower FM, CAF, and leptin in women, suggesting that beneficial changes in leptin can be similarly achieved through different dietary approaches to BW loss.

Peritoneal fluid and serum leptin concentrations in women with primary infertility

Leptin is proposed to participate in the reproductive system of women by acting on either ovaries or hypothalamic-pituitary axis. The objective of the present study is to investigate the leptin concentrations in peritoneal fluid and serum samples of women diagnosed with primary infertility. A prospective study was carried out in women who underwent laparoscopy within the diagnostic process of primary infertility between January 2005 and January 2007. Leptin concentrations were determined in blood samples obtained before surgery and in peritoneal fluid samples collected during laparoscopy. Peritoneal fluid was obtained from 112 subjects; 21 with unexplained infertility 28 with polycystic ovary syndrome (PCOS), 30 with bilateral tubal occlusion, and 33 with endometriosis. Subjects with PCOS have significantly higher body weights, BMI values and plasma leptin levels when compared to other study groups. Peritoneal fluid levels of leptin were significantly higher in the endometriosis group compared to other three study groups. A positive correlation was found between peritoneal fluid leptin levels and the endometriosis stage (r=0.51, P=0.01). However, plasma leptin levels were unrelated to the disease extent. It might be hypothesized that leptin may be an active factor in the pathogenesis of PCOS and endometriosis, which are two major causes of primary infertility. A mild leptin deficiency in peritoneal environment may interrupt follicular development and ultimately lead to PCOS. Leptin has angiogenic and mitogenic properties, which trigger inflammatory cytokines and eventually result in the development of endometriosis implants. Significantly, higher levels of leptin in peritoneal environments of endometriosis subjects strongly imply the important role of this common pathology.

Metformin treatment does not affect total leptin levels and free leptin index in obese patients with polycystic ovary syndrome

Leptin, particularly in its free form, is deeply involved in the regulation of energy balance. Insulin was suggested to influence plasmatic leptin levels and soluble leptin receptor in humans. However, this study indicates that metformin treatment, although improving insulin levels, does not exert a significant effect on either total leptin level or free leptin index in obese women with hyperinsulinemia and PCOS.

Serum Leptin Concentration, Adiposity, and Body Fat Distribution in Mexican-Americans

Leptin is strongly associated with adiposity and few studies have investigated its role in Mexican-Americans. The aims of this study were to examine the association of serum leptin concentration with adiposity and body fat distribution in Mexican-Americans and to develop a predictive model of serum leptin concentration for this ethnic group. Three hundred fifty-two college students (242 women, 110 men; age 18-30 years) were evaluated in this cross-sectional study. Body fat content was assessed using bioelectrical impedance analysis. Correlation between serum leptin levels and several markers of adiposity and body fat distribution were examined in both men and women. Multiple regression analysis was performed to create the predictive model. Women had higher serum leptin concentrations than men for the same levels of adiposity. After controlling for gender and body fat, only fat mass (FM) expressed in kg, was significantly correlated with serum leptin concentration in men (partial rho = 0.811, p <0.001), whereas body mass index (BMI), hip circumference (HC), and FM expressed in kg, were significantly correlated with serum leptin concentration in women (partial rho = 0.214, p <0.001; partial rho = 0.201, p <0.01; and partial rho = 0.818, p <0.001, respectively). Percent body fat (PBF) was the only significant predictor of serum leptin concentration among men, explaining 42% of the variance in serum leptin concentration. In addition to PBF, waist circumference (WC) and HC were significant predictors of serum leptin concentration among women explaining 65% of the variance in serum leptin concentration. Serum leptin concentration is a function of adiposity as determined by PBF in both Mexican-American men and women. HC and WC are associated with serum leptin concentration in Mexican-American women but not in men. BMI alone should not be used in evaluating the association of serum leptin concentration with body fatness in Mexican-Americans.

Valproate, weight gain and carbohydrate craving: A gender study

To compare the incidence and magnitude of weight gain associated with valproic acid (VPA) monotherapy in male and female epilepsy patients and to determine possible gender-specific differences in frequency of carbohydrate craving, body-composition, glucose homeostasis and lipid metabolism. Epilepsy patients on VPA monotherapy were consecutively recruited at the outpatient clinic of the Department of Neurology, Innsbruck Medical University. Weight gain during VPA-therapy, frequency of carbohydrate craving and physical exercise, sociopsychological problems and family history for diabetes were obtained from all patients. Clinical data also comprised body-impedance analysis, body mass index and waist-to-hip ratio. Morning fasting blood samples were drawn to determine serum leptin, glucose and lipid concentrations, as well as insulin, C-reactive protein and TNF-alpha. One hundred and six patients (55 women) were enrolled in the study. Significant weight gain was seen during VPA-therapy in both genders (each p<0.001) with women experiencing increment of weight more frequently and more pronounced than did men. Analyses of patients who gained weight during VPA-therapy revealed significantly higher serum leptin concentrations in women than in men (p<0.001). Women also revealed significantly higher high-density lipoprotein-cholesterol and lower triglyceride concentrations than men (p=0.004 and 0.014, respectively). Frequency of carbohydrate craving was 25.8% in women and 14.3% in men. More women tried to lose or control weight through diet than did men (22.6% versus 7.1%). Moreover, weight gain as a sociopsychological problem was more numorous in women than in men. Women are more prone to gain weight during VPA therapy though higher frequency of diet and sociopsychological burden than men, which might possibly be related to leptin-resitance and a higher frequency of carbohydrate craving.

Serum leptin concentrations and body adipose measures in older black and white adults

Among US adults, serum leptin concentrations are higher in women than in men and are higher in blacks than in whites independent of anthropometric measures of body fatness. Using radiographic measures of body fat, we determined the best correlates of leptin and whether adiposity can explain sex and race differences in leptin concentrations in older adults. This was a cross-sectional analysis of fasting serum leptin concentrations and body fat measured by dual-energy X-ray absorptiometry (DXA), abdominal computed tomography, and standard anthropometry in 3026 well-functioning 70-79-y-old participants (42% black, 51% women) of the Health, Aging, and Body Composition Study. Geometric mean (+/-SE) leptin concentrations (ng/mL) were higher in the women than in the men (16.5 +/- 0.3 and 5.7 +/- 0.1, respectively) and in the black women than in the white women (20.2 +/- 0.6 and 13.9 +/- 0.4, respectively), but did not differ significantly between the white and black men (5.8 +/- 0.2 and 5.5 +/- 0.2, respectively). Percentage fat estimated from DXA showed the highest correlation with leptin (R(2) = 0.56 for both sexes). Addition of abdominal visceral fat minimally increased the correlation. In the multivariate analysis, the association with sex was eliminated after adjustment for percentage fat and visceral fat in both whites (P = 0.051) and blacks (P = 0.34). Among women, higher leptin concentrations in blacks remained after adjustment for percentage fat and visceral fat (mean race difference = 4.95 ng/mL; P < 0.001). Among men, an association with black race emerged after adjustment for these factors (mean race difference = 1.42 ng/mL; P < 0.001). Among older adults, higher serum leptin concentrations in women are explained by a greater percentage of body fat. Higher leptin concentrations in blacks are not explained by percentage of body fat.

Serum leptin levels correlate with obesity parameters but not with hyperinsulinism in women with polycystic ovary syndrome

To examine serum leptin concentrations in obese and lean patients with polycystic ovary syndrome (PCOS) to assess whether the changes in leptin levels are due to obesity or hormonal alterations. Controlled clinical study. Academic research environment. Obese and lean women with PCOS. Blood samples were collected before and after food consumption. Serum leptin and insulin levels. Serum leptin concentrations were significantly correlated with body mass index (r = 0.649) and also with HOMA (r = 0.535). However, after controlling for body mass index in a partial correlation analysis, no significant correlation was found between serum leptin levels and HOMA or hyperinsulinemia. While lean patients with PCOS had a significant correlation between leptin concentrations and obesity parameters, they did not show any significant correlation with insulin resistance parameters. Although leptin concentrations in women with PCOS correlate with insulin resistance/hyperinsulinemia, this is related only to obesity.

Endothelin 1 and leptin in the pathophysiology of intrauterine growth restriction

Objectives: To evaluate the relationship of endothelin 1 (ET-1) and leptin concentrations in women and newborns following a pregnancy complicated with intrauterine growth restriction (IUGR). Methods: Twenty-five women with a pregnancy complicated with IUGR at 19 different gestational ages were matched with women with uncomplicated pregnancies. Blood samples from the umbilical artery and maternal peripheral venous circulation were collected at delivery, and ET-1 and leptin levels were determined from the blood samples. Data relating to obstetric complications (e.g., pregnancy-induced hypertension), delivery (e.g. mode, birth weight, signs of intrapartum fetal distress, and Apgar scores) were also recorded. Results: Mean maternal ET-1 (13.4±6.2–9.9±2.9 pmol/l) and mean fetal ET-1 (14.5±4.2–11.7±3.1 pmol/l) concentrations were significantly higher when women had experienced pregnancies complicated with IUGR than when they had had normal pregnancies. Mean fetal leptin concentration was significantly lower in the study group (6.8±2.2 ng/ml) than in the control group (10.6±3.6 ng/ml ( P<0.05). However, fetal leptin per kilogram of fetal weight was not significantly different in the study group (3.16±1.18 ng/ml) than in the control group (3.23±0.96 ng/ml) ( P>0.05, paired t-test). However, a statistically significant correlation was observed between fetal leptin concentrations per kilogram of fetal weight and fetal endothelin concentrations in pregnancies complicated with IUGR ( r=0.546; P<0.05). Conclusions: These results suggest the intertwined roles of ET-1 and leptin in the pathophysiology of IUGR. Further studies concerning interaction between these peptides in different pregnancy conditions may provide important information about the actions of ET-1 and leptin on fetal growth.