scholarly journals Hypothalamic administration of sargahydroquinoic acid elevates peripheral thermogenic signaling and ameliorates high fat diet-induced obesity through the sympathetic nervous system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Doyeon Kim ◽  
Yuna Lee ◽  
Hyeung-Rak Kim ◽  
Yeo Jin Park ◽  
Hongik Hwang ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Signaling Pathways ◽  
High Fat Diet ◽  
Energy Homeostasis ◽  
High Fat ◽  
Diet Induced Obesity ◽  
Brown Adipose ◽  
Sympathetic Nervous

AbstractSargassum serratifolium (C. Agardh) C.Agardh, a marine brown alga, has been consumed as a food and traditional medicine in Asia. A previous study showed that the meroterpenoid-rich fraction of an ethanolic extract of S. serratifolium (MES) induced adipose tissue browning and suppressed diet-induced obesity and metabolic syndrome when orally supplemented. Sargahydroquinoic acid (SHQA) is a major component of MES. However, it is unclear whether SHQA regulates energy homeostasis through the central nervous system. To examine this, SHQA was administrated through the third ventricle in the hypothalamus in high-fat diet-fed C57BL/6 mice and investigated its effects on energy homeostasis. Chronic administration of SHQA into the brain reduced body weight without a change in food intake and improved metabolic syndrome-related phenotypes. Cold experiments and biochemical analyses indicated that SHQA elevated thermogenic signaling pathways, as evidenced by an increase in body temperature and UCP1 signaling in white and brown adipose tissues. Peripheral denervation experiments using 6-OHDA indicated that the SHQA-induced anti-obesity effect is mediated by the activation of the sympathetic nervous system, possibly by regulating genes associated with sympathetic outflow and GABA signaling pathways. In conclusion, hypothalamic injection of SHQA elevates peripheral thermogenic signaling and ameliorates diet-induced obesity.

scholarly journals Central Administration of Sargahydroquinoic Acid Elevates Peripheral Thermogenic Signaling and Ameliorates High Fat Diet-Induced Obesity

2021 ◽  
Author(s):  
Doyeon Kim ◽  
Hyeung-Rak Kim ◽  
Yuna Lee ◽  
Hongik Hwang ◽  
Hyewhon Rhim ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Signaling Pathways ◽  
High Fat Diet ◽  
Energy Homeostasis ◽  
Mrna Levels ◽  
Central Administration ◽  
High Fat ◽  
Diet Induced Obesity ◽  
Brown Adipose ◽  
Sargassum Serratifolium

Abstract Sargassum serratifolium (C.Agardh) C.Agardh, a marine brown alga, has been consumed as food and traditional medicine in Asia. A previous study showed that the meroterpenoid-rich fraction of an ethanolic extract of Sargassum serratifolium (MES) induced adipose tissue browning and suppressed diet-induced obesity and metabolic syndrome. Sargahydroquinoic acid (SHQA) is a major component in MES. However, it is unclear whether SHQA can regulate energy homeostasis through the central nervous system. To figure it out, SHQA was administrated through the third ventricle of the hypothalamus in high-fat diet-fed C57BL/6 mice and investigated its effects on energy homeostasis. Bath application of SHQA increases the intrinsic neuronal excitability of hypothalamic ARC neurons in acutely prepared brain slices. Thus, we further tested its effect on energy balance. Chronic administration of SHQA into the brain reduced bodyweight without a change in food intake and improved metabolic syndrome-related phenotypes. Cold experiments and biochemical analyses indicate that SHQA elevates thermogenic signaling pathways evidenced by an increase in body temperature and UCP1 signaling in white and brown adipose tissues. As partial mechanisms, SHQA significantly elevated mRNA levels of genes associated with sympathetic outflow and GABA signaling pathways. Our data indicate that hypothalamic injection of SHQA elevates peripheral thermogenic signaling and ameliorates diet-induced obesity.

scholarly journals Relevance of Sympathetic Nervous System Activation in Obesity and Metabolic Syndrome

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Alicia A. Thorp ◽  
Markus P. Schlaich
Keyword(s):  
Metabolic Syndrome ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Metabolic Control ◽  
Energy Homeostasis ◽  
Metabolic Effects ◽  
Metabolic Abnormalities ◽  
Sympathetic Overactivity ◽  
The Metabolic Syndrome ◽  
Sympathetic Nervous

Sympathetic tone is well recognised as being implicit in cardiovascular control. It is less readily acknowledged that activation of the sympathetic nervous system is integral in energy homeostasis and can exert profound metabolic effects. Accumulating data from animal and human studies suggest that central sympathetic overactivity plays a pivotal role in the aetiology and complications of several metabolic conditions that can cluster to form the Metabolic Syndrome (MetS). Given the known augmented risk for type 2 diabetes, cardiovascular disease, and premature mortality associated with the MetS understanding the complex pathways underlying the metabolic derangements involved has become a priority. Many factors have been proposed to contribute to increased sympathetic nerve activity in metabolic abnormalities including obesity, impaired baroreflex sensitivity, hyperinsulinemia, and elevated adipokine levels. Furthermore there is mounting evidence to suggest that chronic sympathetic overactivity can potentiate two of the key metabolic alterations of the MetS, central obesity and insulin resistance. This review will discuss the regulatory role of the sympathetic nervous system in metabolic control and the proposed pathophysiology linking sympathetic overactivity to metabolic abnormalities. Pharmacological and device-based approaches that target central sympathetic drive will also be discussed as possible therapeutic options to improve metabolic control in at-risk patient cohorts.

scholarly journals Enteric glial cells respond to a dietary change in the lamina propria in a MyD88-dependent manner

2020 ◽  
Author(s):  
Zhuanzhuan Liu ◽  
Hongxiang Sun ◽  
Ming Liang ◽  
Jing Gao ◽  
Liyuan Meng ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Nervous System ◽  
Glial Cells ◽  
High Fat Diet ◽  
Metabolic Disorders ◽  
Neuronal System ◽  
High Fat ◽  
Dietary Shift ◽  
Diet Induced Obesity ◽  
Enteric Glial Cells

AbstractImmune and nervous system sensing are two important ways of detecting inner and outer environmental changes. Immune cell activation in the gut can promote metabolic disorders. However, whether enteric nervous system sensing and activities are also important in metabolic syndromes is not clear. Enteric glial cells (EGCs) are thought to have sensing ability, but little is known about the potential connections between EGC and metabolic disorders. Consuming a modern Western-type high-fat low-fiber diet increases the risk of obesity. Here, we reported that dietary shift from a normal chow diet to a high-fat diet in wild-type (WT) C57BL/6 mice induced a transient emergence of glial fibrillary acidic protein (GFAP)-positive EGC network in the ileal lamina propria, accompanied by an increase of glial-derived neurotrophic factors production. Inhibition of EGC metabolic activity via gliotoxin fluorocitrate or glial-intrinsic deletion of myeloid differentiation factor 88 (Myd88) in mice blocked this dietary change-induced activity. Furthermore, we found a different role of MYD88 in glial cells versus adipocyte in diet-induced obesity. The glial Myd88 knockout mice gained less body weight after HFD feeding compared to the littermate controls. In contrast, adipocyte deletion of Myd88 in mice had no impact on the weight gain but had exacerbated glucose metabolic disorders. Pharmacological interventions of glial activities by fluorocitrate prevented body weight gain in a dietary type- and glial MYD88-independent manner. Collectively, our data reveal a previously unappreciated function of EGC in sensing a dietary shift-induced perturbation and glial activities as a whole may play roles in diet-induced obesity.New & NoteworthyIt is known that obesity and its related metabolic syndrome can damage the neuronal system. However, whether the neuronal system also participates in the development of obesity is unclear. Diet is an important contributing factor to obesity. Our study reveals that consuming a high-fat diet can induce a transient enteric glial cell response via its intrinsic sensing molecule(s). Inhibiting overall glial cell activities may have an impact on the development of the metabolic syndrome.

CNS origins of the sympathetic nervous system outflow to brown adipose tissue

1999 ◽  
Vol 276 (6) ◽  
pp. R1569-R1578 ◽  
Author(s):  
Maryam Bamshad ◽  
C. Kay Song ◽  
Timothy J. Bartness
Keyword(s):  
Nervous System ◽  
Adipose Tissue ◽  
Sympathetic Nervous System ◽  
Brown Adipose Tissue ◽  
Pseudorabies Virus ◽  
Critical Role ◽  
Hypothalamic Nucleus ◽  
Brown Adipose ◽  
Sympathetic Nervous ◽  
Diet Induced Thermogenesis

Brown adipose tissue (BAT) plays a critical role in cold- and diet-induced thermogenesis. Although BAT is densely innervated by the sympathetic nervous system (SNS), little is known about the central nervous system (CNS) origins of this innervation. The purpose of the present experiment was to determine the neuroanatomic chain of functionally connected neurons from the CNS to BAT. A transneuronal viral tract tracer, Bartha’s K strain of the pseudorabies virus (PRV), was injected into the interscapular BAT of Siberian hamsters. The animals were killed 4 and 6 days postinjection, and the infected neurons were visualized by immunocytochemistry. PRV-infected neurons were found in the spinal cord, brain stem, midbrain, and forebrain. The intensity of labeled neurons in the forebrain varied from heavy infections in the medial preoptic area and paraventricular hypothalamic nucleus to few infections in the ventromedial hypothalamic nucleus, with moderate infections in the suprachiasmatic and lateral hypothalamic nuclei. These results define the SNS outflow from the brain to BAT for the first time in any species.

Tissue-specific increase in norepinephrine turnover by central interleukin-1, but not by interleukin-6, in rats

1994 ◽  
Vol 266 (2) ◽  
pp. R400-R404 ◽  
Author(s):  
A. Terao ◽  
M. Oikawa ◽  
M. Saito
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Interleukin 1 ◽  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Interscapular Brown Adipose Tissue ◽  
Norepinephrine Turnover ◽  
Brown Adipose ◽  
Intracerebroventricular Injections ◽  
Sympathetic Nervous

To examine the effects of brain cytokines on the sympathetic nervous system, norepinephrine (NE) turnover in peripheral organs (spleen, lung, diaphragm, pancreas, heart, liver, kidney, and interscapular brown adipose tissue) was assessed after intraperitoneal or intracerbroventricular administrations of human recombinant interleukin (IL)-1 beta and IL-6 in rats. An intraperitoneal injection of IL-1 (1 microgram/rat) accelerated NE turnover in the spleen, lung, diaphragm, and pancreas without appreciable effects in other organs examined. When IL-1 was injected intracerebroventricularly at much lower doses (1-100 ng/rat), a dose-dependent increase in NE turnover was observed in the spleen, lung, diaphragm, and pancreas. IL-6 did not affect NE turnover in every organ examined, even when it was given at much higher doses, 100 micrograms/rat and 100 ng/rat for intraperitoneal and intracerebroventricular injections, respectively. In contrast to tissue NE turnover, plasma corticosterone level was increased after the administration of IL-6 as well as IL-1, regardless of the site of administration. These results suggest that central IL-1, but not IL-6, increases sympathetic nerve activity in some specific organs, whereas both cytokines are effective for adrenocortical activation. A possible role of the sympathetic nervous system in physiological and immune responses to central IL-1 was discussed.

scholarly journals MicroRNAs Regulating Renin–Angiotensin–Aldosterone System, Sympathetic Nervous System and Left Ventricular Hypertrophy in Systemic Arterial Hypertension

Biomolecules ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1771
Author(s):  
Alex Cleber Improta-Caria ◽  
Marcela Gordilho Aras ◽  
Luca Nascimento ◽  
Ricardo Augusto Leoni De Sousa ◽  
Roque Aras-Júnior ◽  
...  
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Left Ventricular Hypertrophy ◽  
Signaling Pathways ◽  
Ventricular Hypertrophy ◽  
Left Ventricular ◽  
Renin Angiotensin Aldosterone System ◽  
Renin Angiotensin ◽  
Gene And Protein Expression ◽  
Sympathetic Nervous

MicroRNAs are small non-coding RNAs that regulate gene and protein expression. MicroRNAs also regulate several cellular processes such as proliferation, differentiation, cell cycle, apoptosis, among others. In this context, they play important roles in the human body and in the pathogenesis of diseases such as cancer, diabetes, obesity and hypertension. In hypertension, microRNAs act on the renin–angiotensin–aldosterone system, sympathetic nervous system and left ventricular hypertrophy, however the signaling pathways that interact in these processes and are regulated by microRNAs inducing hypertension and the worsening of the disease still need to be elucidated. Thus, the aim of this review is to analyze the pattern of expression of microRNAs in these processes and the possible associated signaling pathways.

scholarly journals IL-15Rα is a determinant of muscle fuel utilization, and its loss protects against obesity

2015 ◽  
Vol 309 (8) ◽  
pp. R835-R844 ◽  
Author(s):  
Emanuele Loro ◽  
Erin L. Seifert ◽  
Cynthia Moffat ◽  
Freddy Romero ◽  
Manoj K. Mishra ◽  
...  
Keyword(s):  
High Fat Diet ◽  
Energy Homeostasis ◽  
Wide Distribution ◽  
Liver Fat ◽  
Acid Oxidation ◽  
Direct Effects ◽  
High Fat ◽  
Binding Partner ◽  
Insulin Resistant ◽  
Diet Induced Obesity

IL-15Rα is the widely expressed primary binding partner for IL-15. Because of the wide distribution in nonlymphoid tissues like skeletal muscle, adipose, or liver, IL-15/IL-15Rα take part in physiological and metabolic processes not directly related to immunity. In fast muscle, lack of IL-15Rα promotes an oxidative switch, with increased mitochondrial biogenesis and fatigue resistance. These effects are predicted to reproduce some of the benefits of exercise and, therefore, improve energy homeostasis. However, the direct effects of IL-15Rα on metabolism and obesity are currently unknown. We report that mice lacking IL-15Rα (IL-15Rα−/−) are resistant to diet-induced obesity (DIO). High-fat diet-fed IL-15Rα−/− mice have less body and liver fat accumulation than controls. The leaner phenotype is associated with increased energy expenditure and enhanced fatty acid oxidation by muscle mitochondria. Despite being protected against DIO, IL-15Rα−/− are hyperglycemic and insulin-resistant. These findings identify novel roles for IL-15Rα in metabolism and obesity.

Diminished sympathetic nervous system activity in genetically obese (ob/ob) mouse

1983 ◽  
Vol 245 (2) ◽  
pp. E148-E154 ◽  
Author(s):  
J. B. Young ◽  
L. Landsberg
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Cold Exposure ◽  
Feedback Regulation ◽  
Turnover Rates ◽  
Interscapular Brown Adipose Tissue ◽  
Peripheral Tissues ◽  
Brown Adipose ◽  
Sympathetic Nervous ◽  
Long Acting

The genetically obese (ob/ob) mouse exhibits defective thermoregulatory responses to cold exposure. Pathophysiological explanations for this phenomenon have focused on abnormalities in intracellular metabolism or insensitivity of peripheral tissues to the thermogenic effects of catecholamines. Because the sympathetic nervous system (SNS) is subject to feedback regulation, a peripheral impairment in thermogenesis should be associated with a compensatory increase in SNS activity. To examine SNS activity in the ob/ob mouse, norepinephrine (NE) turnover was measured in heart and interscapular brown adipose tissue (IBAT) of ob/ob and lean mice. The results from studies utilizing radiolabeled NE or inhibition of NE biosynthesis with alpha-methyl-p-tyrosine to measure NE turnover demonstrated reductions in SNS activity of 33-56% in heart and of 45-73% in IBAT in ob/ob mice at ambient temperature (22 degrees C) compared with measurements in lean controls. During cold exposure (4 degrees C) NE turnover increased in heart and IBAT to a similar extent in both ob/ob and lean mice, but NE turnover rates in heart, and probably in IBAT as well, remained lower in the obese mice than in the lean despite the gradual development of hypothermia in the ob/ob mice during this period. Administration of naltrexone, a long-acting opiate antagonist, failed to reverse the suppression of SNS activity observed in the ob/ob mice. These data indicate that diminished SNS activity in ob/ob mice may be an additional factor contributing to the defective thermogenesis characteristic of these animals.

Sign in / Sign up

Export Citation Format

Share Document