OBJECTIVEConditioned taste preference (CTP) is a taste learning reflex by which an animal learns to prefer a substance which tastes not well and has been studied with much interest in recent years. However, the neural substrates of CTP are less known. This study aimed to determine the possible neural path- ways of CTP and whether serum leptin level and the leptin receptor (OB-Rb) in the hind brain are involved following CTP formation.

METHODSWe established CTP of quinine in rats with a 2-bottle preference test. The serum leptin concentrations were detected, the expression of c-fos in the rat brain was tested to determine the nuclei in relation with establishment of CTR Finally, the OB-Rb mRNA expression was examined by RT-qPCR assay in parabrachial nucleus (PBN) and the nucleus of the solitary tract (NST) of the hind brain.

RESULTSCompared with control group, the level of serum leptin was higher in the CTP group (4.58 ± 0.52 vs 1.67 ± 0.25 µg/L, P < 0.01); increased c-fos positive cells were found in the anterior hypothalamus (AH, 221.75 ± 4.96 vs. 178.50 ± 6.63 cells/mm², P < 0.05), the basal lateral amygdala (BLA, 70.75 ± 6.17 vs 56.50 ± 3.62 cells/ mm², P < 0.05) and the nucleus of the solitary tract (NST, 41.25 ± 1.32 vs 32.50 ± 1.02 cells/mm², P < 0.05). But in ventromedial nucleus of the hypothalamus (VMH, 20.75 ± 2.73 vs 38.5 ± 1.54 per 1 mm², P < 005), PBN (21.50 ± 2.24 vs 36.25 ± 1.49 cells/mm², P < 0.05) and the central nucleus of the amygdala (CeA, 22.25 ± 1.53 vs 35.50 ± 2.11 cells/mm², P < 0.05), the number of c-fos positive cells was decreased in the CTP group. In addition, we found OB-Rb mRNA expression in PBN of CTP group rats was higher than that of control group (0.95 ± 0.055 vs 0.57 ± 0.034, P < 0.05), while there was no significant difference of OB-Rb mRNA expression in NST between the two groups.

CONCLUSIONNuclei AH, BLA, NST, VMH, PBN and CeA participate in the formation of CTP. Leptin and its receptor in PBN may be involved in the formation and maintenance of CTP.

Animals ; Conditioning (Psychology) ; Leptin ; blood ; Rats ; Receptors, Leptin ; physiology ; Rhombencephalon ; physiology ; Taste ; physiology

OBJECTIVETo observe effects of acupuncture on BMI, WHR and serum levels of leptin and neuropeptide Y in simple obesity Uigur patients to research the mechanism of acupuncture in slimming.

METHODSThirty simple obesity Uigur patients were treated with body acupuncture combined with electroacupuncture. Two courses later, their therapeutic effects were observed. And the above indexes were determined before and after treatment.

RESULTSThe clinical total effective rate was 80.00%, and BMI, WHR, and the serum leptin level decreased (P < 0. 001).

CONCLUSIONUigur patients of simple obesity possibly exist resistance of leptin and acupuncture can decrease the peripheral leptin content.

Acupuncture Therapy ; Electroacupuncture ; Humans ; Leptin ; blood ; Neuropeptide Y ; Obesity ; therapy

AIMTo determining whether the level of serum leptin altered and whether the expression of leptin receptor immunoreactivity changed following taste stimuli.

METHODSAfter intraoral infusions of chemical solutions, which included 3 mol/L sucrose, 5 mmol/L sodium saccharin, 0.1 mol/L NaCl, 0.01 mol/L HCl, 1 mmol/L quinine H2SO4 and 0.1 mol/L monosodium glutamate, serum leptin concentration were measured by using rat leptin RIA kit. Immunohistochemistry ABC method was used for brain sections with high-specify-goat antiserum against leptin receptors.

RESULTSComparing with the control group (intraoral infusion of distilled water), the level of serum leptin only in sweet group (sucrose an d saccharin) raised (P < 0.05). Many neuronal cell bodies and dendritic processes showed leptin receptors immunoreactivity (LR-IR) in many brain regions, such as amygdala, hypothalamus, parabrachial nucleus and nucleus of the solitary tract, which had intense relationship with taste and feeding. But the number of positive-stained cells showed no difference in aforementioned brain regions between the taste stimuli group and the control group.

CONCLUSIONAfter intraoral stimuli of sweet substances, the serum leptin concentration increased. LR-IR cells exist in amygdala which plays a critical role in the initiation and guidance of feeding. This findings led us study possible effects of leptin on taste responses. Probably, leptin influences food intake through the sense of taste.

Animals ; Brain ; physiology ; Eating ; Female ; Leptin ; blood ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Receptors, Leptin ; blood ; Taste

OBJECTIVETo compare the slimming effects of electroacupuncture of different frequencies.

METHODSThe rats were randomly divided into a control group, a model group, an acupuncture group I (30 Hz), and an acupuncture group II (100 Hz). Acupoints selected were "Housanli" (ST 36), "Sanyinjiao" (SP 6), "Guanyuan" (CV 4), "Zhongwan" (CV 12). The changes of Lee's index, fat weight around the left kidney and the volume of the fat cell, blood lipids, insulin and leptin before and after treatment were compared.

RESULTSCompared with the model group, Lee's index, fat weight around the left kidney and the volume of the fat cell, blood lipids significantly changed in the two acupuncture groups (P<0.01), with the acupuncture group II being more change than that of the acupuncture group I (P<0.05); and compared with the model group, the leptin level decreased in the two acupuncture group (P<0.01) and the serum insulin level decreased (P<0.05) , with no significant difference between the acupuncture group I and the acupuncture group II (P>0.05).

CONCLUSIONElectroacupuncture of different frequencies has different effects on fat metabolism in fat rats, and electroacupuncture of 100 Hz has a better effect than 30 Hz on obesity.

Animals ; Electroacupuncture ; methods ; Insulin ; blood ; Leptin ; blood ; Lipids ; blood ; Obesity ; blood ; therapy ; Rats ; Rats, Sprague-Dawley

Animals ; Biomarkers ; blood ; Fatty Liver ; blood ; etiology ; Humans ; Leptin ; blood ; Obesity ; blood ; complications

Adult ; Aged ; Anthracosis ; blood ; Humans ; Leptin ; blood ; Male ; Middle Aged ; Resistin ; blood

Adult ; Female ; Humans ; Leptin ; blood ; genetics ; Male ; Middle Aged ; Obesity ; blood ; RNA, Messenger ; blood

OBJECTIVESome research has shown that C-reactive protein (CRP), leptin, soluble leptin receptor (sLR) and blood lipids are involved in the development of obesity. This study aimed to investigate the changes of leptin resistance, blood lipids and inflammatory response before and after the exercise therapy in children with obesity.

METHODSFifty-one obese children at ages of 12 years received an exercise therapy for 2 months. The levels of serum leptin, sLR, triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-sensitivity C-reactive protein (hs-CRP) were measured before and after the exercise therapy. Forty normal children served as the control group.

RESULTSCompared with the control group, serum levels of leptin, TG, TC, LDL-C and hs-CRP and the body mass index (BMI) in the obese group increased (p<0.01), while the serum level of sLR decreased significantly (p<0.05). The levels of hs-CRP, leptin, TC, TG, LDL-C and BMI in the obese group were significantly reduced after the exercise therapy (p<0.05). In the obese group, the serum leptin level was positively correlated with the levels of blood lipids and hs-CRP (p<0.05); serum levels of leptin and hs-CRP were negatively correlated with the sLR level (p<0.05); the hs-CRP level was positively correlated with the levels of blood lipids (p<0.01).

CONCLUSIONSLeptin resistance and the changes of blood lipids and inflammatory response are found in children with obesity. Exercise therapy can partially improve these changes.

Body Mass Index ; C-Reactive Protein ; analysis ; Child ; Exercise Therapy ; Female ; Humans ; Leptin ; blood ; Lipids ; blood ; Male ; Obesity ; blood ; therapy ; Receptors, Leptin ; blood

OBJECTIVETo evaluate the association between serum level of leptin and leptin receptor gene (LEPR) polymorphism and patients with breast cancer.

METHODSLEPR G1n223Arg polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism in 94 patients with breast cancer and 128 healthy controls. The level of leptin were analyzed by enzyme linked immunosorbent assay.

RESULTSIn univariate regression analyses, we found serum level of leptin and LEPR Gin223Arg genotype polymorphism were significantly higrer than those of the controls (P < 0.05-0.001, respectively). Through multivariable analyses, we found that increased risk estimates for breast cancer were among those with leptin level (OR = 1.53, 95% CI: 1.13-2.07, P = 0.006), LEPR Gin223Arg genotype (OR = 4.87, 95%CI:1.30-18.22, P = 0.019), WHR (OR = 3.68, 95% CI: 1.34-10.11, P = 0.011).

CONCLUSIONResults from this study suggested that LEPR Gln233Agr polymorphism, the elevated WHR and serum level of leptin might be correlated with increased risk of breast cancer.

Breast Neoplasms ; blood ; genetics ; Enzyme-Linked Immunosorbent Assay ; Female ; Genetic Predisposition to Disease ; Humans ; Leptin ; blood ; Lipids ; blood ; Polymorphism, Genetic ; Receptors, Leptin ; genetics ; Risk

OBJECTIVETo explore the changes of serum leptin, soluble leptin receptor (SOB-R) concentrations and free leptin index (FLI) throughout the puberty in females, and estimate the effects of genetic and environmental factors on these indices.

METHODSThe population studied consists of 180 pairs of twins in 6 to 18 years old: 132 pairs of monozygotic twins and 48 pairs of dizygotic twins, who were all from Qingdao city, Shandong Province. Anthropometric and sexual characteristics were examined, fasting serum leptin and SOB-R contents were assayed by immunoradiometric assay and ELISA respectively.

RESULTSSerum leptin concentrations increased and SOB-R decreased throughout puberty (P < 0.05), brought out a sustained increase of FLI, especially in 7-9 and 12-14 years old (from 10.1 to 32.3 and 41.8 to 82.1 respectively); Leptin and FLI were positively, and SOB-R negatively correlated with morphological indices (correlation coefficients from 0.54 to 0.76, -0.23 to -0.42, respectively). Heritability of girl's serum leptin, SOB-R and FLI were 0.37, 0.84, 0.46 respectively.

CONCLUSIONSSerum free leptin index surge at 7-9 and 12-14 years old might be a predictor or trigger of the puberty onset and menarche, respectively; FLI might be determined by both genetic and environmental factors. Leptin should be substantially influenced by environment and reflect the fat mass of body compositions. SOB-R should be predominantly controlled by genetic factors yet. Genetic influence might be important in pubertal development and metabolic disorders.

Adolescent ; Child ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Immunoradiometric Assay ; Leptin ; blood ; Puberty ; blood ; Receptors, Leptin ; blood ; Twins, Dizygotic ; Twins, Monozygotic