Estrogen increases in vivo leptin production in rats and human subjects

1997 ◽  
Vol 154 (2) ◽  
pp. 285-292 ◽  
Author(s):  
H Shimizu ◽  
Y Shimomura ◽  
Y Nakanishi ◽  
T Futawatari ◽  
K Ohtani ◽  
...  

Abstract The decrease in estrogen in menopausal women increases body fat. The present studies were undertaken to investigate the involvement of estrogen in leptin production in vivo. In the first study, expression of ob gene mRNA in white adipose tissue was measured at 2 and 8 weeks after ovariectomy in rats. In the second, serum leptin concentration was measured in total body fat of 87 weight-matched human subjects (29 men, 29 premenopausal and 29 postmenopausal women). In the third, changes in serum leptin concentration with the menstrual cycle were determined, ob gene expression decreased in subcutaneous and retroperitoneal white adipose tissue of ovariectomized rats 8 weeks after the operation, while ovariectomy increased ob gene expression in mesenteric white adipose tissue. Serum leptin concentration was decreased by ovariectomy. Estradiol supplement reversed the effect of ovariectomy on ob gene expression and circulating leptin levels. In humans, serum leptin concentration was higher in premenopausal women than in men, and in postmenopausal women it was lower than in premenopausal women, but still higher than in men. In 13 premenopausal women, serum leptin levels were significantly higher in the luteal phase than in the follicular phase. The present studies strongly indicate that estrogen regulates leptin production in rats and human subjects in vivo. Regional variation in the regulation of ob gene expression by estrogen was found. Journal of Endocrinology (1997) 154, 285–292

2021 ◽  
Vol 11 (9) ◽  
pp. 874
Author(s):  
Sunghwun Kang ◽  
Kyu-Min Park ◽  
Kun-Young Sung ◽  
Yuning Yuan ◽  
Seung-Taek Lim

Physical exercise may stimulate lipolytic activity within adipose tissue. Furthermore, resistance exercise may contribute to the more efficient reduction in adipose tissue mass and prevent the accumulation thereof in obese women. The purpose of this study was to examine the effects of regular resistance exercise for 12 weeks on the lipolysis pathway in women with obesity. Twenty-three pre- and postmenopausal women with body fat percentages of 30% or more were divided into the premenopausal group (n = 9) and the postmenopausal group (n = 14). All subjects participated in resistance exercise training for 12 weeks. Anthropometric and physical fitness tests were performed on all participants. Protein analyses were performed on extracted subcutaneous fatty tissue, and changes in the relevant protein levels in the samples were analyzed by Western blotting. All serum samples were submitted for enzyme-linked immunosorbent assay measurements of adipocyte factors. After 12 weeks, the adipose triglyceride lipase, monoacylglycerol lipase, and perilipin1 protein levels were significantly lower in the postmenopausal group than in the premenopausal group. The hormone-sensitive lipase protein levels were significantly higher in the postmenopausal group than in the premenopausal group. In addition, leptin concentrations were significantly decreased after resistance exercise in the postmenopausal group. Adiponectin concentrations were significantly increased after resistance exercise in both groups. These findings indicate that regular resistance exercise is effective in reducing the weight and body fat of obese premenopausal women, and in the secretion of adiponectin. On the other hand, postmenopausal women were found to have redeced weight and body fat, and were found to be positive for the secretion of adipokine factors. In addition, positive changes in lipolysis pathway factors in adipose tissue promote lipid degradation and reduce fat mass. Thus, regular resistance exercise shows positive changes in the lipolysis pathway more effectively in weight and body fat reduction in postmenopausal women than in premenopausal women.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A52-A52
Author(s):  
Anna Goddi ◽  
Alanis Carmona ◽  
Liesl Schroedl ◽  
Matthew J Piron ◽  
Jeremy M White ◽  
...  

Abstract As research into the adipocyte microenvironment has advanced, it is becoming more widely accepted that the extracellular matrix (ECM) contributes to adipocyte dysfunction. The majority of current published work focuses on the role of collagens in metabolic disease while less emphasis has been placed on the contribution of laminins, an important component of the adipocyte basement membrane. Laminins are trimeric ECM proteins composed of α, β, and γ chains. The α chains contain sites which can interact with cell surface receptors and is considered the driver of tissue-specific expression and specialized signaling. Our group has shown that the laminin-α4 (LAMA4) chain, which is highly expressed in mature adipocytes, plays a role in adipocyte function and thermogenesis in mice (1). In this study we investigate the relationship between laminin α chain expression and obesity by assessing gene expression of LAMA1-5 in subcutaneous white adipose tissue (sWAT) from mice fed chow (RCD) and 45% high fat diet (HFD) for 8 weeks. Expression of LAMA2 and LAMA4 was significantly increased in the HFD sWAT compared to chow (6.1 fold, p=0.01 and 4.9 fold, p=0.001 respectively), however LAMA4 displayed a much stronger positive correlation with weight (R2=0.697) than did LAMA2 (R2=0.382). In order to validate the relevance of these findings in human models of obesity, we evaluated gene expression of LAMA2, LAMA4, and LAMA5 in sWAT biopsies from non-diabetic adult females with obesity (class II or higher). sWAT samples from obese subjects exhibited 4.5 fold higher LAMA4 expression (p=0.0089) than samples from non-obese control subjects, suggesting that the LAMA4 chain may play an important role in human obesity. Lastly we examined changes in sWAT LAMA4 expression following a period of weight loss in obese mice and in human subjects after bariatric surgery, and found that LAMA4 expression levels remain largely unchanged in both cases. In this study we demonstrate the relationship between LAMA4 expression and obesity and present findings that can be extended to human models of obesity. Reference: (1) Vaicik et al., Endocrinology. 2018 Jan;159(1):356–67.


2010 ◽  
Vol 70 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Katherine E. Pinnick ◽  
Fredrik Karpe

Body fat distribution plays an important role in determining metabolic health. Whereas central obesity is closely associated with the development of CVD and type 2 diabetes, lower body fat appears to be protective and is paradoxically associated with improved metabolic and cardiovascular profiles. Physiological studies have demonstrated that fatty acid handling differs between white adipose tissue depots, with lower body white adipose tissue acting as a more efficient site for long-term lipid storage. The regulatory mechanisms governing these regional differences in function remain to be elucidated. Although the local microenvironment is likely to be a contributing factor, recent findings point towards the tissues being intrinsically distinct at the level of the adipocyte precursor cells (pre-adipocytes). The multi-potent pre-adipocytes are capable of generating cells of the mesenchymal lineage, including adipocytes. Regional differences in the adipogenic and replicative potential of these cells, as well as metabolic and biochemical activity, have been reported. Intriguingly, the genetic and metabolic characteristics of these cells can be retained through multiple generations when the cells are cultured in vitro. The rapidly emerging field of epigenetics may hold the key for explaining regional differences in white adipose tissue gene expression and function. Epigenetics describes the regulation of gene expression that occurs independently of changes in DNA sequence, for instance, DNA methylation or histone protein modification. In this review, we will discuss the contribution of DNA methylation to the determination of cells of adipogenic fate as well as the role DNA methylation may play during adipocyte terminal differentiation.


Cell Reports ◽  
2020 ◽  
Vol 33 (1) ◽  
pp. 108228 ◽  
Author(s):  
John M. Dean ◽  
Anyuan He ◽  
Min Tan ◽  
Jun Wang ◽  
Dongliang Lu ◽  
...  

2000 ◽  
Vol 279 (6) ◽  
pp. R2329-R2335 ◽  
Author(s):  
Paul Trayhurn ◽  
Jacqueline S. Duncan ◽  
Anne M. Wood ◽  
John H. Beattie

White adipose tissue (WAT) has been examined to determine whether the gene encoding metallothionein (MT), a low-molecular-weight stress response protein, is expressed in the tissue and whether MT may be a secretory product of adipocytes. The MT-1 gene was expressed in epididymal WAT, with MT-1 mRNA levels being similar in lean and obese ( ob/ ob) mice. MT-1 mRNA was found in each of the main adipose tissue sites (epididymal, perirenal, omental, subcutaneous), and there was no major difference between depots. Separation of adipocytes from the stromal-vascular fraction of WAT indicated that the MT gene (MT-1 and MT-2) was expressed in adipocytes themselves. Treatment of mice with zinc had no effect on MT-1 mRNA levels in WAT, despite strong induction of MT-1 expression in the liver. MT-1 gene expression in WAT was also unaltered by fasting or norepinephrine. However, administration of a β3-adrenoceptor agonist, BRL-35153A, led to a significant increase in MT-1 mRNA. On differentiation of fibroblastic preadipocytes to adipocytes in primary culture, MT was detected in the medium, suggesting that the protein may be secreted from WAT. It is concluded that WAT may be a significant site of MT production; within adipocytes, MT could play an antioxidant role in protecting fatty acids from damage.


2011 ◽  
Vol 12 (1) ◽  
pp. 136
Author(s):  
M. Saukko ◽  
E. Malo ◽  
M. Santaniemi ◽  
M. Hietaniemi ◽  
O. Ukkola ◽  
...  

2002 ◽  
Vol 10 (6) ◽  
pp. 555-558 ◽  
Author(s):  
Michael Boschmann ◽  
Götz Krupp ◽  
Friedrich C. Luft ◽  
Susanne Klaus ◽  
Jens Jordan

Sign in / Sign up

Export Citation Format

Share Document