scholarly journals Leptin: a pleitropic factor in physiology

2019 ◽  
Vol 4 (2) ◽  
pp. 31
Author(s):  
Fayez A Almabhouh ◽  
Faizatul Isyraqiah Ahmad Muhammad ◽  
Hisham Ibrahim ◽  
Harbindarjeet Singh
Keyword(s):  
Energy Balance ◽  
Sexual Maturation ◽  
Leptin Receptor ◽  
Tertiary Structure ◽  
Serum Levels ◽  
The Body ◽  
Endocrine Function ◽  
Signalling Pathways ◽  
Percentage Body Fat ◽  
Class 1

Leptin, a 16 kDa protein and a product of the ob/ob gene, has a tertiary structure similar to that of a cytokine. It is primarily secreted by white adipose tissue and its levels in the blood correlate positively with percentage body fat. Leptin was first identified in 1994 as a major factor that regulated food intake and energy balance. Leptin in the circulation exists either as a free monomeric hormone or bound to its soluble receptor. Its serum levels usually range from 0.5 to 37.7 ng/ml in males and 2.0 to 45.2 ng/ml in females. The half-life of leptin is between 20 - 30 minutes and it is eliminated mainly by the kidneys. However, research over the last 25 years has revealed numerous other physiological roles for leptin, including roles in inflammation, immune function, neuro-endocrine function, bone metabolism, blood pressure regulation and sexual maturation. Most of these roles have been identified from studies on leptin deficient rodents. Apart from energy balance and sexual maturation, where its role is direct and obvious, its actions on the rest of the other systems are permissive. Actions of leptin are both centrally and peripherally mediated involving receptors that are widely distributed in the body. Six leptin receptor isoforms, belonging to the class 1 cytokine receptor family, have been identified. These receptors are products of the OBR gene. The cellular actions of leptin are mediated through any one of five different signalling pathways that include the JAK-STAT, PI3K, MAPK, AMPK, and the mTOR signalling pathways.

Relative leptin deficiency in children with severe early-onset obesity (SEOO) – results of the Early-onset Obesity and Leptin – German-Polish Study (EOL-GPS)

2020 ◽  
Vol 33 (2) ◽  
pp. 255-263 ◽  
Author(s):  
Agnieszka Zachurzok ◽  
Michael B. Ranke ◽  
Bertram Flehmig ◽  
Katarzyna Jakubek-Kipa ◽  
Katarzyna Marcinkiewicz ◽  
...  
Keyword(s):  
Early Onset ◽  
Leptin Receptor ◽  
Standard Deviation Score ◽  
Tanner Stage ◽  
Serum Levels ◽  
The Body ◽  
Biologically Active ◽  
World Health ◽  
Strong Negative Correlation ◽  
Leptin Deficiency

AbstractBackgroundSevere early-onset obesity (SEOO) in children is a common feature of monogenic obesity. Gene defects of the leptin-melanocortin pathway can be analysed biochemically and genetically. The aim of this study was to search for children with leptin deficiency or biologically inactive leptin in a cohort of children with SEOO and to study associations between leptin parameters and anthropometric data.MethodsThe cohort included n = 50 children with SEOO (22 boys) who were recruited at one of four study centres (Germany: Ulm; Poland: Katowice, Szczecin, Rzeszow) between October 2015 and October 2017. Weight (kg) and height (m) were measured, Tanner stage was obtained and a fasting serum blood sample was taken. Serum levels of total leptin (LEP, ng/mL), biologically active leptin (bioLEP, ng/mL) and soluble leptin receptor (sLEPR, ng/mL) were measured. The body mass index (BMI [kg/m2]), BMI z-score (World Health Organization [WHO]), quotient of bioLEP/LEP and leptin-standard deviation score (LEP-SDS) (Tanner stage, BMI and sex-adjusted) were calculated.ResultsWe did not find any child with leptin deficiency or biologically inactive leptin in our cohort. The serum LEP and bioLEP levels were strongly correlated with age (r = 0.50, p < 0.05) and BMI (r = 0.70; p < 0.0001). Girls had higher LEP and bioLEP levels (49.7 ± 35.9 vs. 37.1 ± 25.5 ng/mL, p > 0.05) as well as lower LEP-SDS than boys (−1.77 ± 2.61 vs. −1.40 ± 2.60, p > 0.05). sLEPR levels were negatively correlated with BMI values (r = −0.44; p < 0.05), LEP (r = −0.39; p < 0.05) and bioLEP levels (r = −0.37; p < 0.05). Interestingly, there was a strong inverse relationship between LEP-SDS and BMI (r = −0.72, p < 0.001).ConclusionsIn this cohort with SEOO, we identified no new cases of children with leptin deficiency or bioinactive leptin. A strong negative correlation between the LEP-SDS and BMI values could be interpreted as relative leptin deficiency in children with SEOO. In case this hypothesis can be confirmed, these children would benefit from a substitution therapy with methionyl human leptin (metreleptin™).

Changes in Body Composition, Energy Metabolism, and Appetite-Regulating Hormones in Korean Professional Female Ballet Dancers Before and After Ballet Performance

2019 ◽  
Vol 23 (4) ◽  
pp. 173-180
Author(s):  
Soo Youn Kim ◽  
Jung Ho Cho ◽  
Ji Hyun Lee ◽  
Jae Hyun Jung
Keyword(s):  
Body Composition ◽  
Energy Balance ◽  
Energy Intake ◽  
Body Mass ◽  
Serum Levels ◽  
The Body ◽  
Blood Analysis ◽  
Ballet Dancers ◽  
Before And After ◽  
Dependent Sample

This study investigated changes in body composition, energy balance, and appetite-regulating hormones in professional female ballet dancers before and after 3 days of ballet performances. The subjects were 43 professional female ballet dancers in Korea. The mean age of the subjects was 25.9 ± 2.8 years, and they had over 13 years of ballet training on average. For body composition, the body mass index (BMI), percent body fat (%BF), lean body mass (LBM), and total body water (TBW) were evaluated. By way of blood analysis the serum levels of ghrelin, leptin, and insulin were examined. The calculations of energy intake (EI) and expenditure (EE) were based on journals that were self-recorded by the subjects for 14 days. For statistical analysis, the dependent sample t-test was applied (p < 0.05). The results showed no significant change in %BF, but the BMI, LBM, and TBW increased significantly in the post-performance measurement. Energy balance results demonstrated a significant increase in EI and decrease in EE. Both the ghrelin and leptin levels increased significantly. Although reported energy intake increased after performances, it remained below estimated energy requirements. Ballet dancers should be aware of the need to maintain energy balance in order to optimize their health and performance.

scholarly journals Identification of the Long-Sought Leptin in Chicken and Duck: Expression Pattern of the Highly GC-Rich Avian leptin Fits an Autocrine/Paracrine Rather Than Endocrine Function

Endocrinology ◽  
2015 ◽  
Vol 157 (2) ◽  
pp. 737-751 ◽  
Author(s):  
Eyal Seroussi ◽  
Yuval Cinnamon ◽  
Sara Yosefi ◽  
Olga Genin ◽  
Julia Gage Smith ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Energy Balance ◽  
Leptin Receptor ◽  
Expression Patterns ◽  
Structural Similarity ◽  
Adult Brain ◽  
Endocrine Function ◽  
Rt Pcr

Abstract More than 20 years after characterization of the key regulator of mammalian energy balance, leptin, we identified the leptin (LEP) genes of chicken (Gallus gallus) and duck (Anas platyrhynchos). The extreme guanine-cytosine content (∼70%), the location in a genomic region with low-complexity repetitive and palindromic sequence elements, the relatively low sequence conservation, and low level of expression have hampered the identification of these genes until now. In vitro-expressed chicken and duck leptins specifically activated signaling through the chicken leptin receptor in cell culture. In situ hybridization demonstrated expression of LEP mRNA in granular and Purkinje cells of the cerebellum, anterior pituitary, and in embryonic limb buds, somites, and branchial arches, suggesting roles in adult brain control of energy balance and during embryonic development. The expression patterns of LEP and the leptin receptor (LEPR) were explored in chicken, duck, and quail (Coturnix japonica) using RNA-sequencing experiments available in the Short Read Archive and by quantitative RT-PCR. In adipose tissue, LEP and LEPR were scarcely transcribed, and the expression level was not correlated to adiposity. Our identification of the leptin genes in chicken and duck genomes resolves a long lasting controversy regarding the existence of leptin genes in these species. This identification was confirmed by sequence and structural similarity, conserved exon-intron boundaries, detection in numerous genomic, and transcriptomic datasets and characterization by PCR, quantitative RT-PCR, in situ hybridization, and bioassays. Our results point to an autocrine/paracrine mode of action for bird leptin instead of being a circulating hormone as in mammals.

L-Ascorbic Acid Addition to Chitosan Reduces Body Weight in Overweight Women

2014 ◽  
Vol 84 (1-2) ◽  
pp. 5-11 ◽  
Author(s):  
Eun Y. Jung ◽  
Sung C. Jun ◽  
Un J. Chang ◽  
Hyung J. Suh
Keyword(s):  
Ascorbic Acid ◽  
Body Weight ◽  
Fat Body ◽  
Body Weight Gain ◽  
Skinfold Thickness ◽  
The Body ◽  
Control Group ◽  
Percentage Body Fat ◽  
Overweight Women ◽  
Body Weights

Previously, we have found that the addition of L-ascorbic acid to chitosan enhanced the reduction in body weight gain in guinea pigs fed a high-fat diet. We hypothesized that the addition of L-ascorbic acid to chitosan would accelerate the reduction of body weight in humans, similar to the animal model. Overweight subjects administered chitosan with or without L-ascorbic acid for 8 weeks, were assigned to three groups: Control group (N = 26, placebo, vehicle only), Chito group (N = 27, 3 g/day chitosan), and Chito-vita group (N = 27, 3 g/day chitosan plus 2 g/day L-ascorbic acid). The body weights and body mass index (BMI) of the Chito and Chito-vita groups decreased significantly (p < 0.05) compared to the Control group. The BMI of the Chito-vita group decreased significantly compared to the Chito group (Chito: -1.0 kg/m2 vs. Chito-vita: -1.6 kg/m2, p < 0.05). The results showed that the chitosan enhanced reduction of body weight and BMI was accentuated by the addition of L-ascorbic acid. The fat mass, percentage body fat, body circumference, and skinfold thickness in the Chito and Chito-vita groups decreased more than the Control group; however, these parameters were not significantly different between the three groups. Chitosan combined with L-ascorbic acid may be useful for controlling body weight.

Ghrelin and Obesity-An Update

2017 ◽  
Vol 9 (1) ◽  
Author(s):  
Gandhi M. ◽  
Swaminathan S.
Keyword(s):  
Diabetes Mellitus ◽  
Cardiac Output ◽  
Energy Balance ◽  
Vascular Resistance ◽  
The Body ◽  
Ghrelin Receptor ◽  
Type2 Diabetes ◽  
Type2 Diabetes Mellitus ◽  
Natural Hormones

Ghrelin as human natural hormones is involved in fundamental regulatory process of eating and energy balance. It is a stomach derived hormone that acts as at the ghrelin receptor in multiple tissues throughout to the body. Its properties includes increasing appetite, decreasing systemic inflammation, decreasing vascular resistance ,increasing cardiac output, increasing glucose and IGF-1 levels, Hence it may play a significant role in Diabetes mellitus. Many studies have linked ghrelin to obesity and this paper is an attempt to bring out recent findings on the role of ghrelin in Diabetes Mellitus, particularly type2 Diabetes mellitus.

scholarly journals The metabolic hormone leptin promotes the function of TFH cells and supports vaccine responses

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jun Deng ◽  
Qian Chen ◽  
Zhian Chen ◽  
Kaili Liang ◽  
Xin Gao ◽  
...  
Keyword(s):  
Leptin Receptor ◽  
Serum Levels ◽  
Affinity Maturation ◽  
Antibody Responses ◽  
Vaccine Failure ◽  
Vaccine Responses ◽  
Follicular Helper ◽  
B Virus ◽  
And Function ◽  
Metabolic Hormone

AbstractFollicular helper T (TFH) cells control antibody responses by supporting antibody affinity maturation and memory formation. Inadequate TFH function has been found in individuals with ineffective responses to vaccines, but the mechanism underlying TFH regulation in vaccination is not understood. Here, we report that lower serum levels of the metabolic hormone leptin associate with reduced vaccine responses to influenza or hepatitis B virus vaccines in healthy populations. Leptin promotes mouse and human TFH differentiation and IL-21 production via STAT3 and mTOR pathways. Leptin receptor deficiency impairs TFH generation and antibody responses in immunisation and infection. Similarly, leptin deficiency induced by fasting reduces influenza vaccination-mediated protection for the subsequent infection challenge, which is mostly rescued by leptin replacement. Our results identify leptin as a regulator of TFH cell differentiation and function and indicate low levels of leptin as a risk factor for vaccine failure.

scholarly journals Ovarian tissue freezing and activation after thawing: an update

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Li-fan Peng
Keyword(s):  
Granulosa Cells ◽  
Clinical Decision Making ◽  
Ovarian Function ◽  
Ovarian Tissue ◽  
Clinical Decision ◽  
The Body ◽  
Endocrine Function ◽  
Ovarian Tissue Cryopreservation ◽  
Main Body ◽  
Tissue Cryopreservation

Abstract Background With the growth of women’s age, ovarian failure can be caused by various factors. For the women who need chemotherapy because of cancer factors, the preservation of fertility is more urgent. The treatment of cancer is also a process in which all tissues and organs of the body are severely damaged, especially in the reproductive system. Main body As a new fertility preservation technology, autologous ovarian tissue cryopreservation and transplantation is developing rapidly and showing great potentiality in preserving ovarian endocrine function of young cervical cancer patients. Vitrification and slow freezing are two common techniques applied for ovarian tissue cryopreservation. Thus, cryopreserved/thawed ovarian tissue and transplantation act as an important method to preserve ovarian function during radiotherapy and chemotherapy, and ovarian cryopreservation by vitrification is a very effective and extensively used method to cryopreserve ovaries. The morphology of oocytes and granulosa cells and the structure of organelles were observed under the microscope of histology; the hormone content in the stratified culture medium of granulosa cells with the diameter of follicle was used to evaluate the development potential of ovarian tissue, and finally the ovarian tissue stimulation was determined by the technique of ovarian tissue transplantation. Conclusions Although there are some limitations, the team members still carry out this review to provide some references and suggestions for clinical decision-making and further clinical research.

scholarly journals A Comprehensive Spectroscopic Analysis of the Ibuprofen Binding with Human Serum Albumin, Part II

2021 ◽  
Vol 89 (3) ◽  
pp. 30
Author(s):  
Anna Ploch-Jankowska ◽  
Danuta Pentak ◽  
Jacek E. Nycz
Keyword(s):  
Fatty Acids ◽  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Tertiary Structure ◽  
Temperature Characteristic ◽  
The Body ◽  
Structural Modifications ◽  
Influence Of Temperature On ◽  
Exogenous Substances

Human serum albumin (HSA) is the most abundant human plasma protein. HSA plays a crucial role in many binding endos- and exogenous substances, which affects their pharmacological effect. The innovative aspect of the study is not only the interaction of fatted (HSA) and defatted (dHSA) human serum albumin with ibuprofen (IBU), but the analysis of the influence of temperature on the structural modifications of albumin and the interaction between the drug and proteins from the temperature characteristic of near hypothermia (308 K) to the temperature reflecting inflammation in the body (312 K and 314 K). Ibuprofen is a non-steroidal anti-inflammatory drug. IBU is used to relieve acute pain, inflammation, and fever. To determine ibuprofen’s binding site in the tertiary structure of HSA and dHSA, fluorescence spectroscopy was used. On its basis, the fluorescent emissive spectra of albumin (5 × 10−6 mol/dm3) without and with the presence of ibuprofen (1 × 10−5–1 × 10−4 mol/dm3) was recorded. The IBU-HSA complex’s fluorescence was excited by radiation of wavelengths of λex 275 nm and λex 295 nm. Spectrophotometric spectroscopy allowed for recording the absorbance spectra (zero-order and second derivative absorption spectra) of HSA and dHSA under the influence of ibuprofen (1 × 10−4 mol/dm3). To characterize the changes of albumin structure the presence of IBU, circular dichroism was used. The data obtained show that the presence of fatty acids and human serum albumin temperature influences the strength and type of interaction between serum albumin and drug. Ibuprofen binds more strongly to defatted human serum albumin than to albumin in the presence of fatty acids. Additionally, stronger complexes are formed with increasing temperatures. The competitive binding of ibuprofen and fatty acids to albumin may influence the concentration of free drug fraction and thus its therapeutic effect.

scholarly journals Type 3 Deiodinase Role on Central Thyroid Hormone Action Affects the Leptin-Melanocortin System and Circadian Activity

Endocrinology ◽  
2016 ◽  
Vol 158 (2) ◽  
pp. 419-430 ◽  
Author(s):  
Zhaofei Wu ◽  
M. Elena Martinez ◽  
Donald L. St. Germain ◽  
Arturo Hernandez
Keyword(s):  
Energy Balance ◽  
Elevated Serum ◽  
Serum Levels ◽  
Leptin Resistance ◽  
Melanocortin System ◽  
White Adipocyte ◽  
Pituitary Thyroid Axis ◽  
Thyroid Axis ◽  
The Central Nervous System ◽  
Type 3

Abstract The role of thyroid hormones (THs) in the central regulation of energy balance is increasingly appreciated. Mice lacking the type 3 deiodinase (DIO3), which inactivates TH, have decreased circulating TH levels relative to control mice as a result of defects in the hypothalamic-pituitary-thyroid axis. However, we have shown that the TH status of the adult Dio3−/− brain is opposite that of the serum, exhibiting enhanced levels of TH action. Because the brain, particularly the hypothalamus, harbors important circuitries that regulate metabolism, we aimed to examine the energy balance phenotype of Dio3−/− mice and determine whether it is associated with hypothalamic abnormalities. Here we show that Dio3−/− mice of both sexes exhibit decreased adiposity, reduced brown and white adipocyte size, and enhanced fat loss in response to triiodothyronine (T3) treatment. They also exhibit increased TH action in the hypothalamus, with abnormal expression and T3 sensitivity of genes integral to the leptin-melanocortin system, including Agrp, Npy, Pomc, and Mc4r. The normal to elevated serum levels of leptin, and elevated and repressed expression of Agrp and Pomc, respectively, suggest a profile of leptin resistance. Interestingly, Dio3−/− mice also display elevated locomotor activity and increased energy expenditure. This occurs in association with expanded nighttime activity periods, suggesting a disrupted circadian rhythm. We conclude that DIO3-mediated regulation of TH action in the central nervous system influences multiple critical determinants of energy balance. Those influences may partially compensate each other, with the result likely contributing to the decreased adiposity observed in Dio3−/− mice.

PRE-MATERNAL ISOLATION EFFECTS ON BEHAVIOUR AND ENDOCRINE FUNCTION OF OFFSPRING

1969 ◽  
Vol 62 (2) ◽  
pp. 367-384 ◽  
Author(s):  
A. M. Sackler ◽  
A. S. Weltman ◽  
R. Schwartz ◽  
P. Steinglass
Keyword(s):  
Locomotor Activity ◽  
Growth Rates ◽  
Female Offspring ◽  
The Body ◽  
Endocrine Function ◽  
Male And Female ◽  
Isolation Stress ◽  
Developmental Growth ◽  
Body Weights ◽  
And Control

ABSTRACT This report was designed to determine combined effects of maternal endocrine imbalances and abnormal behaviour due to prolonged isolation stress of female mice on the behaviour, developmental growth rate and endocrine function of their offspring. Sixty female albino mice averaging 19 g were divided equally into isolated and control groups. The isolated females were housed singly; control females were maintained in groups of 2 mice per cage. After observation of behavioural and physiological effects characteristic of isolation stress in the test mice, all isolated and control mice were mated after a 6½ month experimental, isolation period. No differences were observed in fertility and fecundity of the two groups of mothers. Analyses of developmental growth rates of the litters of the isolated versus control mothers showed significantly lower body weights in the test offspring at 3 and 4 weeks of age. The body weights of the female offspring remained significantly lower from the 4th to 11th weeks. The effects on the body weights of the male offspring declined and were no longer statistically significant at the 5th to 11 weeks. Locomotor activity at 4½ and 8 weeks of age was markedly or significantly higher in the male and female mice from isolated mothers. Tail-blood samples taken prior to autopsy at 5 and 11 weeks of age revealed significant decreases in the total leukocyte and eosinophil counts of both sexes. At the two ages, the absolute and relative spleen and thymus weights of the male and female offspring were markedly and/or significantly lower than the values observed in counterpart young from control females. Significant decreases were also observed in the absolute gonadal organ weights of both sexes at 11 weeks of age. The various data indicated inhibited growth rates, heightened locomotor activity and evasiveness, as well as evidence of increased adrenocortical function in the offspring from test mothers. The gonadal weight decreases suggested retarded gonadal development. Further studies using split-litter techniques are required to differentiate the effects of prenatal endocrine imbalances versus postnatal maternal influence (i. e., nursing care) on the offspring.

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