• 제목/요약/키워드: Energy homeostasis

검색결과 146건 처리시간 0.025초

Identification of a neural pathway governing satiety in Drosophila

  • Min, Soohong;Chung, Jongkyeong
    • BMB Reports
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    • 제49권3호
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    • pp.137-138
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    • 2016
  • Satiety cues a feeding animal to cease further ingestion of food, thus protecting it from excessive energy gain. Impaired control of satiety is often associated with feeding-related disorders such as obesity. In our recent study, we reported the identification of a neural pathway that expresses the myoinhibitory peptide (MIP), critical for satiety responses in Drosophila. Targeted silencing of MIP neuron activity strikingly increased the body weight (BW) through elevated food intake. Similarly, genetic disruption of the gene encoding MIP also elevated feeding and BW. Suppressing the MIP pathway behaviorally transformed the satiated flies to feed similar to the starved ones, with augmented sensitivity to food. Conversely, temporal activation of MIP neuron markedly reduced the food intake and BW, and blunted the sensitivity of the starved flies to food as if they have been satiated. Shortly after termination of MIP neuron activation, the reduced BW reverted to the normal level along with a strong feeding rebound. Together our results reveal the switch-like role of the MIP pathway in feeding regulation by controlling satiety.

Hsp20, a Small Heat Shock Protein of Deinococcus radiodurans, Confers Tolerance to Hydrogen Peroxide in Escherichia coli

  • Singh, Harinder;Appukuttan, Deepti;Lim, Sangyong
    • Journal of Microbiology and Biotechnology
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    • 제24권8호
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    • pp.1118-1122
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    • 2014
  • The present study shows that DR1114 (Hsp20), a small heat shock protein of the radiation-resistant bacterium Deinococcus radiodurans, enhances tolerance to hydrogen peroxide ($H_2O_2$) stress when expressed in Escherichia coli. A protein profile comparison showed that E. coli cells overexpressing D. radiodurans Hsp20 (EC-pHsp20) activated the redox state proteins, thus maintaining redox homeostasis. The cells also showed increased expression of pseudouridine (psi) synthases, which are important to the stability and proper functioning of structural RNA molecules. We found that the D. radiodurans mutant strain, which lacks a psi synthase (DR0896), was more sensitive to $H_2O_2$ stress than wild type. These suggest that an increased expression of proteins involved in the control of redox state homeostasis along with more stable ribosomal function may explain the improved tolerance of EC-pHsp20 to $H_2O_2$ stress.

음양기혈대사(陰陽氣血代謝)와 비만(肥滿)의 상관관계 (Correlation between Eum, Yang, Ki and Blood Metabolism and Obesity)

  • 신순식
    • 동의생리병리학회지
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    • 제33권1호
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    • pp.1-9
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    • 2019
  • This paper aims to present a model of obesity and leanness based on eum, yang, ki and blood metabolism of Korean medicine. I analyzed the theory of eum, yang, ki and blood metabolism, yang transforming ki and eum forming the body on Korean medicine, and compared them with energy homeostasis by anabolism and catabolism of modern medicine. In the eum and yang theory, the metabolic process of the human body is dominated by synergism and antagonism between eum force and yang force. When the balance of eum and yang collapses, all the pathological actions of the human body appear, and in the eum and yang metabolic process, an imbalance between yang transforming ki and eum forming the body occurs. The function of yang transforming ki is reduced to ki deficiency, and the function of eum forming the body is increased to blood excess. When blood excess and ki deficiency is given, energy intake increases, energy expenditure decreases, overweight and obesity occur. On the contrary, the function of yang transforming ki is increased to ki excess, and the function of eum forming the body is decreased to blood deficiency. When ki excess and blood deficiency is done, energy intake decreases and energy expenditure increases, the body becomes leanness. When the balance of eum, yang, ki and blood metabolism collapses and becomes blood excess and ki deficiency, overweight and obesity occur, and when ki excess and blood deficiency is done, the body becomes leanness. The energy homeostasis of the human body can be explained by eum, yang, ki and blood metabolism of Korean medicine and it contains the concept of anabolism and catabolism of modern medicine.

Mutation of the lbp-5 gene alters metabolic output in Caenorhabditis elegans

  • Xu, Mo;Choi, Eun-Young;Paik, Young-Ki
    • BMB Reports
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    • 제47권1호
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    • pp.15-20
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    • 2014
  • Intracellular lipid-binding proteins (LBPs) impact fatty acid homeostasis in various ways, including fatty acid transport into mitochondria. However, the physiological consequences caused by mutations in genes encoding LBPs remain largely uncharacterized. Here, we explore the metabolic consequences of lbp-5 gene deficiency in terms of energy homeostasis in Caenorhabditis elegans. In addition to increased fat storage, which has previously been reported, deletion of lbp-5 attenuated mitochondrial membrane potential and increased reactive oxygen species levels. Biochemical measurement coupled to proteomic analysis of the lbp-5(tm1618) mutant revealed highly increased rates of glycolysis in this mutant. These differential expression profile data support a novel metabolic adaptation of C. elegans, in which glycolysis is activated to compensate for the energy shortage due to the insufficient mitochondrial ${\beta}$-oxidation of fatty acids in lbp-5 mutant worms. This report marks the first demonstration of a unique metabolic adaptation that is a consequence of LBP-5 deficiency in C. elegans.

Manganese and Iron Interaction: a Mechanism of Manganese-Induced Parkinsonism

  • Zheng, Wei
    • 한국환경성돌연변이발암원학회지
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    • 제23권4호
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    • pp.115-130
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    • 2003
  • Idiopathic Parkinson's disease (IPD) represents a common neurodegenerative disorder. While epidemiological studies have suggested a number of risk factors including age, gender, race, and inherited disorder, the cumulative evidence supports the view that environmental or occupational exposure to certain chemicals may contribute to the initiation and progress of Parkinsonism. More recently, clinical and laboratory investigations have led to the theory that dysregulation of iron, an essential metal to body function, may underlie IPD by initiating free radical reaction, diminishing the mitochondrial energy production, and provoking the oxidative cytotoxicity. The participation of iron in neuronal cell death is especially intriguing in that iron acquisition and regulation in brain are highly conservative and thus vulnerable to interference from other metals that bear the similar chemical reactivity. Manganese neurotoxicity, induced possibly by altering iron homeostasis, is such an example. In fact, the current interest in manganese neurotoxicology stems from two primary concerns: its clinical symptoms that resemble Parkinson's disease and its increased use as an antiknock agent to replace lead in gasoline. This article will commence with addressing the current understanding of iron-associated neurodegenerative damage. The major focus will then be devoted to the mechanism whereby manganese alters iron homeostasis in brain.

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The Interface Between ER and Mitochondria: Molecular Compositions and Functions

  • Lee, Soyeon;Min, Kyung-Tai
    • Molecules and Cells
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    • 제41권12호
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    • pp.1000-1007
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    • 2018
  • Mitochondria and endoplasmic reticulum (ER) are essential organelles in eukaryotic cells, which play key roles in various biological pathways. Mitochondria are responsible for ATP production, maintenance of $Ca^{2+}$ homeostasis and regulation of apoptosis, while ER is involved in protein folding, lipid metabolism as well as $Ca^{2+}$ homeostasis. These organelles have their own functions, but they also communicate via mitochondrial-associated ER membrane (MAM) to provide another level of regulations in energy production, lipid process, $Ca^{2+}$ buffering, and apoptosis. Hence, defects in MAM alter cell survival and death. Here, we review components forming the molecular junctions of MAM and how MAM regulates cellular functions. Furthermore, we discuss the effects of impaired ER-mitochondrial communication in various neurodegenerative diseases.

보기해훈탕(補氣解暈湯)에 관(關)한 문헌적(文獻的) 고찰(考察) (The literatual study on the Bogi haehun-tang(補氣解暈湯))

  • 이정화;유동열
    • 혜화의학회지
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    • 제11권1호
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    • pp.179-191
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    • 2002
  • The literatual study on the Bogi haehun-tang(補氣解暈湯), the results were obtained as follows : 1. Bogihaehun-tang(補氣解暈湯) is reported Fuqingzhu's Gynecology, Qing dynasty at the first and is used when puerperal faintness, a disorder due to deficiency of vital energy and blood and up ward attack of the asthenic yang, or due to lochistisis and blood stasis attacking the heart. 2. Bogihaehun-tang(補氣解暈湯) is composed of Radix Ginseng(人蔘), Radix Astragali, Radix Angelicae sinensis(當歸) Rhizoma Zingiberis praeparatae(乾臺), Spica Schizonepetae(荊芥). 3. Bogihaehun-tang(補氣解暈湯) have an effect on homeostasis by in vigorating the vital energy, a treatment for prolonged bleeding due to deficiency of vital energy(補氣攝血) applicable to the patient suffening from chronic hemorrhagic disease accompanied with the anifestations of the deficiency of vital energy.

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Leptin의 신경생물학 : 섭식의 신경내분비 조절 (Neurobiology of Leptin : Neuroendocrine Regulation of Food Intake)

  • 김승현;조숙행
    • 정신신체의학
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    • 제7권2호
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    • pp.149-157
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    • 1999
  • 인간은 에너지 섭취와 소모에 있어 변동이 심한 편이지만 비교적 일정한 체중을 유지하고 적절하게 섭식행동을 조절한다. 그러나 이러한 조절기전에 문제가 발생하면 비만이나 그 이외의 다른 섭식장애를 일으키게 되며 다양한 후유증을 야기한다. 본 논문에서는 최근에 소개되기 시작한 호르몬인 leptin이 섭식의 조절과 에너지의 항상성을 조절하는데 있어 어떻게 중요한 작용을 하게되는지 조사하여 주로 정신과 영역에서 관심을 기울일 만한 부분에 대해 고찰하고자 한다. Leptin이 처음 발견되었을 때 그 역할은 주로 음식의 섭취를 제한하고 에너지의 소모를 증가시키는 호르몬으로 소개되었지만, 점차 그 이외의 다른 신체 기능 즉, 생식주기나 신경대분기계에도 영향을 미치는 것으로 보고되면서 정선과 영역에서 차지하는 비중도 확대되고 있다. 그러나 leptin의 작용기전은 매우 복잡하며 많은 부분이 아직도 불분명한 상태에 있다. 이에 저자들은 중추신경계에서 현재까지 알려진 leptin의 작용기전에 대해 살펴보고 섭식과 관련된 그 밖의 다른 신경전달물질들과의 상호작용 그리고 섭식장애와의 관련성에 대해서 최근 문헌들을 조사하여 함께 고찰하고자 한다.

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포유류 생식 내분비 기능 조절에서 Ghrelin의 역할 (Role of Ghrelin in the Control of Reproductive Endocrine Function)

  • 이성호
    • 한국발생생물학회지:발생과생식
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    • 제13권4호
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    • pp.207-215
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    • 2009
  • 시상하부-뇌하수체-생식소(hypothalamus-pituitary-gonad, HPG) 호르몬 축의 활성에 영향을 미치는 수많은 인자들은 생식 기능을 조절하고, 사춘기 개시와 폐경기 진입과 같은 뚜렷한 생식 능력의 단계 전이를 초래한다. 지방세포로부터 분비되는 다기능적 호르몬인 leptin의 발견 이후, 곧 이어 생식과 신체의 에너지 균형 사이의 긴밀한 관계에 대한 증거들이 밝혀졌다. 위장관으로부터 분비되는 또 다른 다기능 호르몬인 ghrelin은 이미 알려져 있던 growth hormone secretagogue receptor(GHSR)의 내인성 리간드이며, 에너지 항상성의 조절에서 leptin에 상응하는 물질로 알려졌다. 예상대로, ghrelin 또한 HPG 축의 활성의 조절을 통해 생식 능력을 조절함이 증명되었다. 이 논문은 ghrelin의 발견과 유전자 구조, 조직 내의 분포, 그리고 역할과 HPG 축에서의 생식 호르몬 분비 조절에 대한 포유동물의 생식에서의 ghrelin-GHSR 신호에 관한 최신 정보를 요약한 것이다. 뇌하수체에서의 POMC 유전자 발현과 유사하게, preproghrelin 유전자는 alternative splicing과 번역 후 변형(posttranslational modification)을 거치는 복잡한 레퍼토리의 전사체들과 펩티드 산물을 만들어 낸다. 에너지 항상성을 제외한 신체 생리 기능의 조절에서의 preproghrelin 유전자 산물의 역할에 관한 정보는 제한적이지만, 신진 대사와 생식 사이에서의 ghrelin의 상호작용에 관해서는 충분한 증거들이 있다. 흰쥐와 인간에서, ghrelin 수용체인 GHSRs(GHSR1a와 GHSR1b)의 분포는 본래 ghrelin의 표적으로 여겨진 시상하부와 뇌하수체뿐만 아니라 정소와 난소에서도 확인되었다. 뇌와 생식소에서도 preproghrelin 유전자 발현이 확인되었는데, 이것은 HPG 축에서 ghrelin이 국부적인 역할을 담당할 가능성을 시사한다. 비록 뇌하수체에서의 기능은 아직 확실치 않지만, ghrelin은 시상하부의 GnRH, 뇌하수체의 생식소자극호르몬과 생식소의 성 스테로이드 호르몬 분비에 대한 음성적인 조절자로서의 역할을 수행하는 것으로 보인다. 최근의 연구들은 사춘기 개시, 그리고 아마도 폐경기 진입의 조절에서 ghrelin의 관여를 시사한다. 이제 ghrelin이 '뇌-위장관' 축의 필수적인 호르몬 요인이며, 신 진 대사와 생식 사이를 연결하는 조절 물질이라는 가능성은 매우 높다. '배부름'을 반영하는 leptin 신호와는 정반대인 ghrelin 신호는 신체 에너지 균형 상태로 볼 때 '배고픔'을 표현하는 것으로 생각되며, 항상성의 유지에서 최우선 사항으로 고려되지 않는 생식으로의 에너지 투자가 이루어지지 않도록 하는데 필수적일 것으로 사료된다. 생식능력 조절에 있어서 ghrelin의 보다 명확한 작용 메커니즘과 역할에 대한 깊은 통찰력을 얻고 성공적인 생의학적 적용을 위해서는 향후 더 많은 연구들이 필요하다.

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Interplay Between Primary Cilia and Autophagy and Its Controversial Roles in Cancer

  • Ko, Je Yeong;Lee, Eun Ji;Park, Jong Hoon
    • Biomolecules & Therapeutics
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    • 제27권4호
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    • pp.337-341
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    • 2019
  • Primary cilia and autophagy are two distinct nutrient-sensing machineries required for maintaining intracellular energy homeostasis, either via signal transduction or recycling of macromolecules from cargo breakdown, respectively. Potential correlations between primary cilia and autophagy have been recently suggested and their relationship may increase our understanding of the pathogenesis of human diseases, including ciliopathies and cancer. In this review, we cover the current issues concerning the bidirectional interaction between primary cilia and autophagy and discuss its role in cancer with cilia defect.