Role of Exercise in the Central Regulation of Energy Homeostasis and in the Prevention of Obesity

AbstractThyroid hormone (TH) regulation is important for development, energy homeostasis, heart function, and bone formation. To control the effects of TH in target organs, the hypothalamus-pituitary-thyroid (HPT) axis and the tissue-specific availability of TH are highly regulated by negative feedback. To exert a central feedback, TH must enter the brain via specific transport mechanisms and cross the blood-brain barrier. Here, tanycytes, which are located in the ventral walls of the 3rd ventricle in the mediobasal hypothalamus (MBH), function as gatekeepers. Tanycytes are able to transport, sense, and modify the release of hormones of the HPT axis and are involved in feedback regulation. In this review, we focus on the relevance of tanycytes in thyrotropin-releasing hormone (TRH) release and review available genetic tools to investigate the physiological functions of these cells.

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The melanocortin system

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00434.2002 ◽

2003 ◽

Vol 284 (3) ◽

pp. E468-E474 ◽

Cited By ~ 264

Author(s):

Ira Gantz ◽

Tung M. Fong

Keyword(s):

Sexual Function ◽

Energy Homeostasis ◽

Melanocortin Receptors ◽

Experimental Basis ◽

Melanocortin System ◽

Genetic Studies ◽

Melanocortin Peptides ◽

Selective Agonists ◽

Made In

The melanocortin system consists of melanocortin peptides derived from the proopiomelanocortin gene, five melanocortin receptors, two endogenous antagonists, and two ancillary proteins. This review provides an abbreviated account of the basic biochemistry, pharmacology, and physiology of the melanocortin system and highlights progress made in four areas. In particular, recent pharmacological and genetic studies have affirmed the role of melanocortins in pigmentation, inflammation, energy homeostasis, and sexual function. Development of selective agonists and antagonists is expected to further facilitate the investigation of these complex physiological functions and provide an experimental basis for new pharmacotherapies.

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L-Carnitine in Drosophila: A Review

Antioxidants ◽

10.3390/antiox9121310 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1310

Author(s):

Maria Rosaria Carillo ◽

Carla Bertapelle ◽

Filippo Scialò ◽

Mario Siervo ◽

Gianrico Spagnuolo ◽

...

Keyword(s):

Transport System ◽

Essential Role ◽

Energy Homeostasis ◽

Current Knowledge ◽

Fatty Acyl ◽

Amino Acid Derivative ◽

Carnitine Transport ◽

Human Transport ◽

Drosophila Models

L-Carnitine is an amino acid derivative that plays a key role in the metabolism of fatty acids, including the shuttling of long-chain fatty acyl CoA to fuel mitochondrial β-oxidation. In addition, L-carnitine reduces oxidative damage and plays an essential role in the maintenance of cellular energy homeostasis. L-carnitine also plays an essential role in the control of cerebral functions, and the aberrant regulation of genes involved in carnitine biosynthesis and mitochondrial carnitine transport in Drosophila models has been linked to neurodegeneration. Drosophila models of neurodegenerative diseases provide a powerful platform to both unravel the molecular pathways that contribute to neurodegeneration and identify potential therapeutic targets. Drosophila can biosynthesize L-carnitine, and its carnitine transport system is similar to the human transport system; moreover, evidence from a defective Drosophila mutant for one of the carnitine shuttle genes supports the hypothesis of the occurrence of β-oxidation in glial cells. Hence, Drosophila models could advance the understanding of the links between L-carnitine and the development of neurodegenerative disorders. This review summarizes the current knowledge on L-carnitine in Drosophila and discusses the role of the L-carnitine pathway in fly models of neurodegeneration.

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The role of short chain fatty acids in appetite regulation and energy homeostasis

International Journal of Obesity ◽

10.1038/ijo.2015.84 ◽

2015 ◽

Vol 39 (9) ◽

pp. 1331-1338 ◽

Cited By ~ 246

Author(s):

C S Byrne ◽

E S Chambers ◽

D J Morrison ◽

G Frost

Keyword(s):

Fatty Acids ◽

Energy Homeostasis ◽

Short Chain Fatty Acids ◽

Short Chain ◽

Appetite Regulation ◽

Chain Fatty Acids

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Organisational Adventures in District Government in Long An Province: Central Regulation Versus Local Initiative

European Journal of East Asian Studies ◽

10.1163/1570061042780874 ◽

2004 ◽

Vol 3 (2) ◽

pp. 279-305

Author(s):

Natalie Hicks

Keyword(s):

Agricultural Development ◽

Central Government ◽

Agricultural Extension ◽

The State ◽

Central Regulation ◽

Socialist Republic ◽

Reform Era ◽

Local Initiative ◽

District Government

AbstractThis article explores the role of district government in agricultural development in Vietnam's Long An province from 1954 to the present. It argues that it is only in the reform era that the district has begun to realise its potential as a 'transmission belt' between the higher authorities and the grassroots. Under the South Vietnamese regime and in the pre-reform era of the Socialist Republic of Vietnam, local initiative was stifled as policy was dictated from on high by central government, with disastrous consequences. In the reform era, district officials have been joined by 'associates of the state', such as agricultural extension officers, to develop innovative 'local' approaches to agricultural development. This has led to increased prosperity but also rising inequality. While the central government has been more willing to allow local experimentation under reform, its influence and interests are still felt, even at the district level. Most scholars emphasise a sharp break between pre-1975 and post-1975 Vietnam. By contrast, this article highlights the way in which there are important elements of continuity both between regimes and between the pre-reform and post-reform eras.

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Plasma Obestatin, Ghrelin, and Ghrelin/Obestatin Ratio Are Increased in Underweight Patients with Anorexia Nervosa But Not in Symptomatic Patients with Bulimia Nervosa

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2008-1138 ◽

2008 ◽

Vol 93 (11) ◽

pp. 4418-4421 ◽

Cited By ~ 57

Author(s):

Palmiero Monteleone ◽

Cristina Serritella ◽

Vassilis Martiadis ◽

Pasquale Scognamiglio ◽

Mario Maj

Keyword(s):

Anorexia Nervosa ◽

Bulimia Nervosa ◽

Energy Homeostasis ◽

Physiological State ◽

Blood Levels ◽

Women Patients ◽

Underweight Patients ◽

Positive Correlations ◽

Clinical Measures

Introduction: Peptides of the gut-brain axis have a pivotal role in the regulation of energy homeostasis. Obestatin, a sibling of ghrelin derived from preproghrelin, is thought to oppose ghrelin effects on food intake. Because changes in ghrelin levels have been associated with anorexia nervosa (AN) and bulimia nervosa (BN), the investigation of obestatin production may further contribute to understanding the role of peripheral peptides in patients with eating disorders. Methods: In the present study, we measured circulating blood levels of obestatin and ghrelin and assessed their relationships with anthropometric and clinical measures in 20 AN patients, 21 BN patients, and 20 appropriate healthy controls. Results: Compared with healthy women, patients with BN showed no significant differences in plasma obestatin and ghrelin concentrations and in the ghrelin/obestatin ratio, whereas underweight AN patients displayed significantly increased circulating levels of both obestatin (P < 0.009) and ghrelin (P < 0.002) and an increased ghrelin/obestatin ratio (P < 0.04). Moreover, in AN women, positive correlations emerged between the ghrelin/obestatin ratio and current body weight and body mass index. Conclusions: Underweight AN patients are characterized by increased concentrations of ghrelin and obestatin and a higher ghrelin to obestatin ratio. No changes in circulating ghrelin or obestatin as well as in ghrelin to obestatin ratio seem to occur in acutely ill patients with BN. Although those changes likely reflect the physiological state of symptomatic AN individuals, they may also contribute to the pathophysiology of the disorder.

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Effects of Kisspeptin-10 on Hypothalamic Neuropeptides and Neurotransmitters Involved in Appetite Control

Molecules ◽

10.3390/molecules23123071 ◽

2018 ◽

Vol 23 (12) ◽

pp. 3071 ◽

Cited By ~ 9

Author(s):

Giustino Orlando ◽

Sheila Leone ◽

Claudio Ferrante ◽

Annalisa Chiavaroli ◽

Adriano Mollica ◽

...

Keyword(s):

Gene Expression ◽

Energy Homeostasis ◽

Hormone Secretion ◽

Reproductive Function ◽

Inhibitory Effect ◽

Bdnf Gene ◽

Appetite Control ◽

Hydroxyindoleacetic Acid ◽

Puberty Onset

Besides its role as key regulator in gonadotropin releasing hormone secretion, reproductive function, and puberty onset, kisspeptin has been proposed to act as a bridge between energy homeostasis and reproduction. In the present study, to characterize the role of hypothalamic kisspeptin as metabolic regulator, we evaluated the effects of kisspeptin-10 on neuropeptide Y (NPY) and brain-derived neurotrophic factor (BDNF) gene expression and the extracellular dopamine (DA), norepinephrine (NE), serotonin (5-hydroxytriptamine, 5-HT), dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIIA) concentrations in rat hypothalamic (Hypo-E22) cells. Our study showed that kisspeptin-10 in the concentration range 1 nM–10 μM was well tolerated by the Hypo-E22 cell line. Moreover, kisspeptin-10 (100 nM–10 μM) concentration independently increased the gene expression of NPY while BDNF was inhibited only at the concentration of 10 μM. Finally, kisspeptin-10 decreased 5-HT and DA, leaving unaffected NE levels. The inhibitory effect on DA and 5-HT is consistent with the increased peptide-induced DOPAC/DA and 5-HIIA/5-HT ratios. In conclusion, our current findings suggesting the increased NPY together with decreased BDNF and 5-HT activity following kisspeptin-10 would be consistent with a possible orexigenic effect induced by the peptide.

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