Serum leptin and lipoprotein levels in women with PCOS.

Weight gain is a common adverse effect associated with the use of most antipsychotic drugs. Leptin has been reported to be associated with antipsychotic-induced weight gain. Previous studies have demonstrated a relationship between the atypical antipsychotics clozapine and olanzapine and serum leptin levels. We planned to comparatively investigate the effects of the atypical antipsychotics quetiapine, olanzapine, risperidone, and clozapine on leptin and triglyceride levels and weight gain. The study population comprised 56 patients with DSM-IV schizophrenia, who were divided into 4 treatment groups: quetiapine (N = 14), olanzapine (N = 14), risperidone (N = 14), or clozapine (N = 14) monotherapy, and a control group of 11 patients receiving no psychopharmacologic treatment. The patients were evaluated at baseline and at the sixth week according to the Positive and Negative Syndrome Scale (PANSS), body mass index (BMI), weight, and fasting serum leptin and triglyceride levels. Data were gathered in 2001 and 2002. Olanzapine and clozapine caused a marked increase in weight and serum triglyceride and leptin levels, though increases in these variables were modest in the patients receiving quetiapine and minimal in those receiving risperidone. There were positive correlations between serum leptin levels and BMI and triglyceride levels. Clinical efficacy, as indicated by decrease in total PANSS scores, was associated with leptin levels in all atypical antipsychotic groups. Our results suggest that leptin may be associated with olanzapine- and clozapine-induced weight gain and that quetiapine appears to have modest influence and risperidone appears to have minimal influence on leptin and triglyceride levels and weight gain compared with olanzapine and clozapine.

Issue Highlights

Epidemiological studies have found obesity to be a risk factor for women's breast cancer. The present study was to investigate whether there is a relationship between serum levels of leptin, insulin, and lipids and breast cancer incidence, in order to find experimental evidence that would be helpful in the diagnosis and prevention of breast cancer. Blood samples were collected from 130 patients with mammary disease and 103 healthy control subjects. Serum leptin, insulin, and lipids were determined by radioimmunoassay (RIA), enzyme-linked immunosorbent assays (ELISA), and Biochemistry Auto-analyzer, respectively. The data analysis was performed by use of the SPSS10.0 computer software. We found that the serum levels of leptin, insulin, and triglyceride (TG) were clearly higher in patients with breast cancer than in patients with benign breast disease and healthy controls, while serum HDL-C levels were lower in breast cancer patients (p < 0.03). Moreover, serum leptin levels were significantly correlated with BMI (body mass index) among three groups, whereas serum insulin levels were unrelated to BMI among three groups. Furthermore, the serum levels of leptin and insulin were not associated with menopausal status in patients with mammary disease (p > 0.05); however, the serum levels of F-Chol, T-Chol, TG, LDL-C, and APOB were significant higher in postmenopausal cases than those in premenopausal cases (p < 0.025). Interestingly, logistic regression analysis showed that subjects with elevated serum levels of leptin, insulin, TG, APOA1, and reduced level of serum HDL-C displayed increased risk of developing breast cancer than those with the normal levels, respectively. In conclusion, the present study suggested that aberrant serum levels of leptin, insulin, and lipids might play an important role in carcinogenesis of breast cancer. The elevated serum levels of leptin, insulin, TG, APOA1, and reduced level of serum HDL-C may be correlated with increased risk of breast cancer, suggesting that one way of preventing breast cancer would be carried out by controlling the intake of food.

Secretion of insulin is compromised in type 2 diabetes (T2DM) individuals and inadequate to accommodate for insulin resistance (IR) in peripheral tissue. Hyperleptinemia reflects leptin resistance, which is a key factor in the production of IR in T2DM patients, making leptin a potential biomarker for evaluating IR levels. The objective of the study was to assess the association of serum leptin and insulin levels among T2DM patients. This case-control research was carried out on T2DM patients. A total of 73 patients diagnosed with T2DM (the case group) and 40 healthy participants (control; group 3) were enrolled according to the American Diabetes Association (ADA) criteria. In the case group, T2DM patients were enrolled with metabolic syndrome (group 1, n = 38) or without metabolic syndrome (group 2, n = 35) according to the WHO criteria. Metabolic profiles of T2DM patients with or without metabolic syndrome were evaluated, and compare these two groups with healthy controls. The subjects of all groups were age- and gender-matched. Body mass index (BMI, P < .01), fasting (P = .0133) and postprandial (P < .01) blood sugar levels, % glycated hemoglobin (HbA1c, P < .01), and lipid profile (P < .01) were found significantly different and higher in group 1 as compared to groups 2 and 3. Serum leptin and insulin levels were found higher and significant in patients with metabolic syndrome (P < .01 for both). The values of serum leptin levels were 10.01 ± 2.7 ng/mL, 6.9 ± 2.4 ng/mL, and 4.11 ± 1.8 ng/mL, and those of serum insulin 120 ± 40.7 µIU/mL, 20.43 ± 5.2 µIU/mL, and 11.4 ± 2.5 µIU/mL in groups 1, 2, and 3, respectively. There was a positive linear correlation between BMI, blood sugar, HbA1c, serum cholesterol (TC), and triglycerides (TG) with serum insulin and leptin levels in the case group. An extremely significant correlation (R = 0.74, P < .001) was found in BMI and serum leptin level in the case group. Serum leptin and insulin levels have a positive association, with serum leptin being a significant predictor of IR syndrome (Evidence Level: 5; Technical Efficacy: Stage 3).

To study the serum leptin and adiponectin levels among relatively healthy older people and their association with traditional cardiovascular risk factors. Personal medical history and blood sample were collected from 1515 older people of Guangzhou. Fasting serum glucose, lipids, leptin and adiponectin were measured. (1) In relatively healthy older adults aged 50 or above, from Guangzhou, the following data were seen: serum leptin levels (x(-) ± s) in men and women were (3.90 ± 2.36) ng/ml and (12.17 ± 2.01) ng/ml respectively; serum adiponectin levels in men and women were (5.33 ± 2.78) mg/L and (7.18 ± 2.58) mg/L respectively. (2) Serum leptin and adiponectin level increased with age. After adjusting for body mass index, the trend for serum leptin level in men (P < 0.001) and adiponectin level in women (P < 0.05) were significantly associated with age. (3) No association was found between cigarette smoking and levels of leptin or adiponectin in both men and women after adjusting for age (P from 0.09 to 0.76). (4) In both men and women, serum leptin and adiponectin levels were positively associated with waist circumference/body mass index, systolic blood pressure, low-density lipoprotein cholesterol and triglyceride (P from 0.04 to < 0.001). In men, leptin was also significantly associated with the increase of diastolic blood pressure and glucose but decreased with high-density lipoprotein cholesterol (P from 0.03 to 0.02). (5) Decreased adiponectin level was associated with increased waist circumference and triglyceride in both men and women (P from 0.003 to < 0.001) and with the increased body mass index, fasting plasma glucose as well as with decreased high-density lipoprotein cholesterol in men (P from 0.05 to < 0.001) but with increased systolic blood pressure and total cholesterol in women (P from 0.05 to 0.006). In Guangzhou city, among relatively healthy older adults aged 50 or above, their serum leptin and adiponectin levels were lower in men than in women. Serum leptin level in men and adiponectin level in women were significantly associated with the increase of age. Increased leptin and decreased adiponectin levels were associated with increased traditional cardiovascular risk factors.

Background Non-alcoholic fatty liver disease (NAFLD) has emerged as the single most common chronic non-viral liver disease. The burden of the disease on healthcare-providing services has increased tremendously. Although a liver biopsy is the most authentic laboratory investigation for scoring the disease progression, it is an invasive technique. Researchers are vigorously working to find alternate markers for the scoring purpose. Despite the importance and association of leptin with metabolic syndrome and its related disorders, there have been relatively fewer studies on serum leptin and its association with NAFLD. Objective This study aimed to investigate variations in serum leptin levels between subjects with and without fibrosisin NAFLD and to assess the predictive value of serum leptin levels in NAFLD subjects. Materials and methods The study comprised 130 NAFLD subjects from two tertiary care hospitals in Lahorealong with 86 healthy controls that were age, gender, and BMI matched with the subjects. Based on the NAFLD fibrosis score (NFS), the subjects were divided into two sub-groups, subjects withsimple steatosis and those with fibrosis. Fasting serum leptin, glucose, and insulin levels were measured using enzyme-linked immunosorbent assay (ELISA). The Kruskal-Wallis test was applied to find differences between the three groups and Fisher's exact test for categorical comparison. To assess the predictive value of serum leptin for steatosis and fibrosis in NAFLD subjects, receiver operation characteristic (ROC) curve analysis was implemented. Results The difference in serum leptin level was statistically highly significant(p-value <0.001), with leptin levels of 10 (17.1) ng/mL among controls, 20.5 (21) ng/mL in simple steatosis, and 21 (28.6) ng/mL in fibrosis. The area under the ROC curve was 0.67 and 0.52 for steatosis and fibrosis, respectively. The cut-off value of 12.2 ng/mL showed 70% sensitivity and 50% specificity for steatosis, while at a threshold of 18 ng/mL, leptin demonstrated 40% sensitivity and specificity for fibrosis. Conclusion In conclusion, this study found that serum leptin levels are higher in NAFLD subjects compared to healthy controls, and it is a good independent predictor for the detection of liver steatosis.

Obesity is characterized by increased storage of fatty acids in an adipose tissue and closely associated with the development of insulin resistance and cardiovascular diseases (CVD) through secretion of adipokines. This study was done to compare serum insulin, leptin, adiponectin and high sensitivity C-reactive protein (hs-CRP) levels according to body masss index (BMI) in Korean adult women aged 19 to 50. In addition, we examined the association of BMI, serum lipids and Homa-IR with serum adiponectin, leptin and hs-CRP levels. The subjects were divided into 3 groups by their BMI, normal weight (BMI ≤ 22.9, n = 30), overweight (23.0 ≤ BMI ≤ 24.9, n = 71) and obese group (25.0 ≤ BMI, n = 59). Serum levels of total-cholesterol, TG, and LDL-cholesterol were significantly higher in obese group than in normal weight group. LDL/HDL ratio and AI were significantly higher in obese group than in normal or overweight group. Fasting serum levels of glucose and insulin and Homa-IR as a marker of insulin resistance were significantly higher in obese group than in overweight group. Serum leptin level was significantly higher in obese group while serum adiponectin level was significantly lower in obese group compared to other two groups. hs-CRP was significantly increased in obese group. Correlation data show that serum adiponectin level was positively correlated with serum HDL- cholesterol level and was negatively correlated with BMI, WC, TG, LDL-cholesterol, Homa-IR, hs-CRP and leptin. In addition, serum leptin level was positively correlated with BMI, WC, glucose, insulin, Homa-IR and hs-CRP. These results might imply that the regulation of key adipokines such as adiponectin might be a strategy for the prevention or treatment of obesity-associated diseases such as diabetes and CVD. (Korean J Community Nutr 16(1) : 126~135, 2011)

Purpose: This randomized clinical trial (RCT) was designed to assess the effect of VD3, n-3FA, and their combination on serum leptin levels in people with vitamin D deficiency (VDD). Subjects and methods: One hundred and forty six participants, were randomly assigned into four groups supplemented with the dose of 50,000 IU VD3 taken weekly (D), 300 mg n-3FA taken daily (Om), and their combination (D+Om) or control (C) for eight weeks. Fasting baseline and follow-up (10 weeks; 8 weeks supplementation plus washout period of 2 weeks) of serum 25 hydroxyvitamin D (25OHD), leptin, glucose, triglycerides (TG), parathyroid hormone (PTH), calcium, and phosphorus were assayed. A paired T-test was used to assess the changes in serum leptin levels over of the follow-up period. Results: Significant increase in follow-up serum leptin (10.62 ± 7.18 to 14.42 ± 8.29 ng/mL, P = 0.002) and TG (154 ± 84.4 to 200.1 ± 79, P = 0.015) levels were observed in n-3-FA supplemented group. Combination therapy (VD3 plus n-3 FA) significantly increased serum 25OHD (13.49 ± 4.64 to 37.09 ± 11.13 ng/mL, P &amp;lt; 0.001), TG levels (114.3 ± 57.3 to 139.1 ± 60.7 mg/mL, P = 0.007) and insignificantly serum leptin (6.74 ± 4.87 to 8.01 ± 6.77 ng/mL, P = 0.269). Conclusion: Our study referred that notable elevation in leptin and TG levels might be linked to leptin resistance. However, further RCTs are required to clarify possible consequences resulted from the extensive administration of n-3FA supplements and their combinations with high doses of VD3 supplements on humans’ health.

P-28: The utility of serum leptin and follicular fluid leptin, estradiol, and progesterone concentrations in infertility patients undergoing in vitro fertilization

Our aim was to determine whether serum leptin level is regulated by thyroid hormones ,lipid metabolic products and insulin resistance status in women with polycystic ovary syndrome (PCOS). A prospectivecase-controlled study was carried out in Istanbul University ,Cerrahpasa School of Medicine in 25 lean PCOS (L-PCOS) women ,19 obese PCOS (O-PCOS) women and 28 normal women. The diagnosis of PCOS was establishedaccording to the clinical ,hormonal (elevated luteinizing hormone and serum androgens) and ultrasonographic findings. Fasting serum levels of thyroid stimulating hormone (TSH) ,free triiodothyronine (FT3),free thyroxine (FT4) ,fasting glucose ,insulin ,total cholesterol (TC) ,triglyceride (TG) ,high-density lipoprotein-cholesterol (HDL-C) ,low-density lipoprotein-cholesterol (LDL-C) ,very low-density lipoprotein-cholesterol(VLDL-C) and leptin were measured and compared in the three groups and the correlations between serum levels of leptin and other parameters were evaluated. Serum leptin levels were higher in the O-PCOSgroup ,while its level was comparable between the L-PCOS and control groups. Serum levels of FT4 were significantly lower in both L-PCOS and O-PCOS groups than the control group. Women in both L-PCOS andO-PCOS groups were found to be significantly hyperinsulinemic and insulin resistant. Serum levels of TC ,VLDL-C and TG were significantly higher in the O-PCOS group ,while serum HDL-C level was lower. Therewas a poor correlation between serum leptin ,and FT4 ,TC ,TG ,HDL-C and VLDL-C levels. A significant correlation was observed between serum leptin levels and both BMI and insulin resistance status in PCOS.We believe that ,although thyroid hormones and lipid metabolic products do not seem to participate in the regulation of serum leptin levels ,BMI and insulin resistance status may have a key role in womenwith PCOS.

The aim of this study was to investigate the changes in serum levels of leptin, cytokines and lipoproteins in women with pre-eclampsia and to evaluate their clinical significance in the pathogenesis of pre-eclampsia. We performed a prospective study involving 45 women with pre-eclampsia in the third trimester of pregnancy and 30 normotensive women in the third trimester of pregnancy. Serum level of leptin was measured by enzyme immunoassay using a Cayman chemical kit. Serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, soluble IL-2 receptor (sIL-2R), IL-6 and IL-8 were measured by using a non-radioimmunoassay chemiluminescent method. Serum lipid concentrations were measured by an Abbott Aeroset (USA) autoanalyzer. Serum levels of apolipoprotein (Apo)A-I and ApoB were evaluated by nephelometrics assays. Differences between groups were evaluated with Student's unpaired t test and, when a variable was not normally distributed, the Mann-Whitney U test was used. The relationship between the variable was explored by the Pearson correlation test. Serum levels of leptin, TNF-α, IL-1β sIL-2R, IL-6 and IL-8 in the pre-eclamptic women were significantly higher than in normotensive women (p < 0.001). In the pre-eclamptic women serum levels of triglycerides, total cholesterol and low-density lipoprotein (LDL)-cholesterol were significantly increased (p < 0.001), while high-density lipoprotein (HDL)-cholesterol and Apo-A were significantly decreased compared to levels in normotensive pregnant women (p < 0.001). No significant differences were noted between the groups in Apo-B (p > 0.05). Serum levels of TNF-α were significantly correlated with the serum levels of IL-6, IL-8, triglycerides, sIL-2R, Apo-A and hematocrit in pre-eclamptic women (r = 0.418, p < 0.05; r = 0.389, p < 0.01; r = 0.312, p < 0.05; r =-0.318, p < 0.05; r =-0.340, p < 0.05 and r = 0.41, p < 0.01, respectively). A negative correlation was seen between serum level of leptin and both IL-1β and Apo-A in pre-eclamptic women (r =-0.44, p < 0.05; r =-0.39, p < 0.05, respectively). Serum levels of IL-6 were also significantly correlated with the serum levels of HDL-cholesterol, LDL-cholesterol and body mass index (BMI) in pre-eclamptic women (r = 0.40, p < 0.01; r =-0.568, p < 0.01; r =-0.30, p < 0.05, respectively). In addition, serum level of IL-8 were significantly correlated with the serum levels of HDL-cholesterol, total cholesterol and BMI in pre-eclamptic women (r = 0.368, p < 0.05; r = 0.513, p < 0.01 and r =-0.41, p < 0.01, respectively). We found that the pre-eclampsia associated with increases in serum levels of leptin, TNF-α, cytokines, triglycerides, total cholesterol and LDL-cholesterol was associated with a significant reduction in serum levels of HDL-cholesterol and Apo-A. These association may be due to the abnormal lipid metabolism and immune activation involved in the pathogenesis of this disease.

To investigate the relationship between serum leptin and lipid profile in South Indian School children and adolescents, and to evaluate the role of serum leptin in obese, overweight and congenital heart diseased children and adolescents; in South Indian population and its correlation with anthropometric and biochemical parameters. The study included 185 school going children and adolescents. (52 obese, 49 overweight, 25 congenital heart disease children and adolescents, were compared with 59 normal controls, aged between 10-17 years). Anthropometric variables, lipid profile, fasting serum glucose were analyzed by autoanalyser and serum leptin by ELISA. Serum leptin levels were significantly elevated in obese and overweight children than in control children (36.88+/-18.60ng/mL, 20.64+/-11.18ng/mL vs 7.97+/-2.79ng/mL; p value <0.001), and decreased in congenital heart diseased children than in control children (6.20+/-4.23 ng/mL vs 7.97+/-2.79ng/mL; p value <0.005). This study provides a good relationship between serum leptin levels and anthropometric and biochemical parameters, such as total cholesterol, triglycerides and LDL-cholesterol. We observed negative correlation between serum leptin and fasting glucose levels and HDL-cholesterol levels were found to be non-significant among the groups. Further studies with large sample size are needed to ascertain the relationship between serum leptin and lipid profile in different groups of children and adolescents.

The enigma of increasing serum leptin levels during peritoneal dialysis.

Background. The reduction mammaplasty has been a well-executed and known procedure in which considerable amount of fatty tissue is removed from the body. The authors aimed to show the effects of the reduction mammaplasty on serum leptin levels and insulin resistance. Methods. 42 obese female patients who had gigantomastia were operated on. We recorded patients' demographic and preoperative data, including age, weight, height, and body mass index. Fasting serum leptin, glucose, and insulin levels were noted. Homeostasis model assessment scores were calculated. At the postoperative 8th week, patients were reevaluated in terms of above parameters assessing the presence of any difference. Results. Serum leptin levels were decreased postoperatively and the decrease was statistically significant. We were able to show a decrease in homeostasis model assessment score, which indicated an increase in insulin sensitivity, and this change was statistically significant. A significant correlation between body mass index and leptin change was found postoperatively. Conclusion. Reduction mammaplasty is not solely an aesthetic procedure but it decreases serum leptin levels and increases insulin sensitivity, which may help obese women to reduce their cardiovascular risk.

The present study analysed the effect of protein restriction on serum insulin and leptin levels and their relationship with energy balance during lactation. Four groups of rats received isocaloric diets containing 170 g protein/kg or 60 g protein/kg from pregnancy until the 14th day of lactation: control non-lactating, control lactating (both fed a control diet), low-protein non-lactating and low-protein lactating. Energy intake, body composition, energy balance, serum insulin and leptin concentrations and the relationship between these hormones and several factors related to obesity were analysed. Low-protein-intake lactating rats exhibited hypoinsulinaemia, hyperleptinaemia, hypophagia and decreased energy expenditure compared with control lactating rats. The protein level in the carcasses was lower in the low-protein lactating group than in the control lactating group, resulting in a higher fat content in the first group compared with the latter. Body fat correlated inversely with serum insulin and positively with serum leptin level. There was a significant negative correlation between serum leptin and energy intake, and a positive relationship between energy intake and serum insulin level in lactating rats and in the combined data from both groups. Energy expenditure was correlated positively with serum insulin and negatively with serum leptin in lactating rats and when data from control non-lactating and lactating rats were pooled. Lactating rats submitted to protein restriction, compared with lactating control rats, showed that maternal reserves were preserved owing to less severe negative energy balance. This metabolic adaptation was obtained, at least in part, by hypoinsulinaemia that resulted in increased insulin sensitivity favouring enhanced fat deposition, hyperleptinaemia and hypophagia.