• Preventive Nutrition and Food Science
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• 제8권1호
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• pp.105-112
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• 2003

Animals possess a highly sophisticated mechanism of storing energy in adipose tissue inside their bodies. However, in humans it has been clarified that adipocyte (fat cell), which composes the body fat (adipose) tissues, development and the extent of subsequent fat accumulation are closely associated with the occurrence and advancement of various common diseases (e.g., type-2 diabetes, coronary artery disease, and hypertension) resulting from obesity. Recent exciting progress in clinical and biochemical studies of adipocytes has rapidly clarified the functions of adipocytes and adipose tissue. Interesting findings are the function of white adipocytes as "secreting cells" and the molecular mechanism undelying adipocyte differentiation at the transcriptional level in relation to nuclear receptors. Consequently, the adipose tissue is being targeted for the prevention or treatment of many common diseases. In this review, I will focus on recent information on characteristics of adipocytes and the relationship between obesity and common obesity-related diseases. diseases.

• BMB Reports
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• 제53권3호
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• pp.142-147
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• 2020

Lipid accumulation in white adipose tissue is the key contributor to the obesity and orchestrates numerous metabolic health problems such as type 2 diabetes, hypertension, atherosclerosis, and cancer. Nonetheless, the prevention and treatment of obesity are still inadequate. Recently, scientists found that brown adipose tissue (BAT) in adult humans has functions that are diametrically opposite to those of white adipose tissue and that BAT holds promise for a new strategy to counteract obesity. In this study, we evaluated the potential of sinapic acid (SA) to promote the thermogenic program and lipolysis in BAT. SA treatment of brown adipocytes induced the expression of brown-adipocyte activation-related genes such as Ucp1, Pgc-1α, and Prdm16. Furthermore, structural analysis and western blot revealed that SA upregulates protein kinase A (PKA) phosphorylation with competitive inhibition by a pan-PKA inhibitor, H89. SA binds to the adenosine triphosphate (ATP) site on the PKA catalytic subunit where H89 binds specifically. PKA-cat-α1 gene-silencing experiments confirmed that SA activates the thermogenic program via a mechanism involving PKA and cyclic AMP response element-binding protein (CREB) signaling. Moreover, SA treatment promoted lipolysis via a PKA/p38-mediated pathway. Our findings may allow us to open a new avenue of strategies against obesity and need further investigation.

• 한국정보통신학회논문지
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• 제17권12호
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• pp.2995-3000
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• 2013

본 연구는 고지방식이를 섭취한 정소절제수술을 한 수컷 마우스에서 백색지방증가의 개선에 대한 testosterone의 영향과 그것에 대한 분자생물학적 조절기전을 규명하였다. Testosterone이 처리된 정소절제수술 마우스(CAST+T)는 정소절제수술 마우스 (CAST)에 비해 지방조직무게, 지방세포크기 및 $C/EBP{\alpha}$와 지방세포 표지유전자의 mRNA 발현이 감소되었다. 본 연구결과는 testosterone이 $C/EBP{\alpha}$와 $C/EBP{\alpha}$에 의해 조절되는 지방세포 표지 유전자들의 발현을 억제시킴으로써 지방세포 조절기전이 억제되고 지방조직의 무게가 감소된다는 것을 시사하고 있다. 따라서 본 연구는 성선기능저하증 남성의 비만조절에 대한 testosterone therapy의 유익한 분자생물학적 정보를 제공할 것이다.

• 대한의생명과학회지
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• 제14권3호
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• pp.139-146
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• 2008

The peroxisome proliferator-activated receptor ${\gamma}$ $(PPAR{\gamma})$ plays a central role in adipogenesis and lipid storage. The $(PPAR{\gamma})$ ligands, thiazolidinediones (TZDs), enhance in vitro adipogenesis in several cell types, but the role of the TZDs on in vivo adipogenesis is still poorly understood. To investigate how $PPAR{\gamma}$ ligand troglitazone regulates adipogenesis in female mice, we examined the effects of the troglitazone on adipose tissue mass, morphological changes of adipocytes, and the expression of $PPAR{\gamma}$ target and adipocyte-specific genes in low fat diet-fed female C57BL/6 mice. Administration of troglitazone for 13 weeks did not change body and total white adipose tissue weights compared with control mice. Troglitazone treatment also did not cause a significant decrease in the average size of adipocytes in parametrial adipose tissue although it is reported to increase the number of small adipocytes in male animals. Troglitazone did not affect the mRNA expression of $PPAR{\gamma}$ and its target genes as well as adipocyte-specific genes in parametrial adipose tissue. These results suggest that $PPAR{\gamma}$ does not seem to be associated with adipogenesis in females with functioning ovaries and that its inability to induce adipogenesis may be due to sex-related factors.

• 대한약침학회지
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• 제20권4호
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• pp.235-242
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• 2017

Irisin is a novel hormone like polypeptide that is cleaved and secreted by an unknown protease from fibronectin type III domain-containing protein 5 (FNDC5), a membrane-spanning protein and which is highly expressed in skeletal muscle, heart, adipose tissue, and liver. Since its discovery in 2012, it has been the subject of many researches due to its potent physiological role. It is believed that understanding irisin's function may be the key to comprehend many diseases and their development. Irisin is a myokine that leads to increased energy expenditure by stimulating the 'browning' of white adipose tissue. In the first description of this hormone, increased levels of circulating irisin, which is cleaved from its precursor fibronectin type III domain-containing protein 5, were associated with improved glucose homeostasis by reducing insulin resistance. Irisin is a powerful messenger, sending the signal to determine the function of specific cells, like skeletal muscle, liver, pancreas, heart, fat and the brain. The action of irisin on different targeted tissues or organs in human being has revealed its physiological functions for promoting health or executing the regulation of variety of metabolic diseases. Numerous studies focus on the association of irisin with metabolic diseases which has gained great interest as a potential new target to combat type 2 diabetes mellitus and insulin resistance. Irisin is found to improve insulin resistance and type 2 diabetes by increasing sensitization of the insulin receptor in skeletal muscle and heart by improving hepatic glucose and lipid metabolism, promoting pancreatic ${\beta}$ cell functions, and transforming white adipose tissue to brown adipose tissue. This review is a thoughtful attempt to summarize the current knowledge of irisin and its effective role in mediating metabolic dysfunctions in insulin resistance and type 2 diabetes mellitus.

• Journal of Microbiology and Biotechnology
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• 제27권4호
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• pp.660-667
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• 2017

PineXol, extracted from Korean red pine bark, has beneficial effects, such as antioxidant, antiinflammatory, and antilipogenic activities in vitro. We tested the hypothesis that PineXol supplementation could have anti-obesity effects on mice fed a high-fat diet (HFD). Four-week-old male C57BL/6 mice were fed normal chow (18% kcal from fat) or a HFD (60% kcal from fat). HFD-fed animals were also subjected to PineXol treatment at a dose of 10 or 50 mg/kg body weight (BW) (PX10 or PX50, respectively) body weight. The body weight and body fat mass in the PX50 group were statistically lower than those in the HFD group (p < 0.05 and p < 0.001, respectively). The concentration of hepatic triglycerides, total cholesterol, and low-density lipoprotein cholesterol were reduced in the PX50 group compared with the HFD group (p < 0.01). Acetyl CoA carboxylase (p < 0.01), elongase of very long chain fatty acids 6 (p < 0.01), stearoyl CoA desaturase 1 (p < 0.05), microsomal triglyceride transfer protein (p < 0.01), and sterol regulatory element-binding protein 1 (p < 0.05) were significantly decreased in the PX50 group compared with that in the HFD group. In white adipose tissue, CCAAT-enhancer-binding protein alpha (p < 0.05), peroxisome proliferator-activated receptor gamma (p < 0.001), and perilipin (p < 0.01) were decreased in the PX50 group compared with those in the HFD group. Therefore, the current study implies the potential of PineXol for the prevention and/or amelioration of obesity, in part by inhibition of both hepatic lipid synthesis and adipogenesis in white adipose tissue.

• Preventive Nutrition and Food Science
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• 제16권3호
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• pp.210-216
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• 2011

Capsaicin is a pungent component of red pepper, which is widely consumed as food adjuncts. The present study was performed to investigate anti-obesity effects of capsaicin in diet-induced obese rats. Male Sprague-Dawley rats (n=14) were fed with a high-fat diet (Control) or high-fat diet containing 0.016% capsaicin (w/w) (Capsaicin) for 8 weeks. The final body weight and the mass of white adipose tissue were significantly lower in capsaicin supplemented group compared to control. Dietary capsaicin ameliorated lipid profiles with decrease in the plasma concentrations of triglycerides and total cholesterol, and decrease in the levels of total lipids and triglycerides in the liver. Activity of glycerol-3-phosphate dehydrogenase (GPDH), an indicator of triglyceride biosynthesis in white adipose tissue, decreased by 35% in the group supplemented with capsaicin. However, consumption of capsaicin increased the expression of uncoupling protein 2 (UCP2) in white adipose tissue, which is related to energy consumption. Our data suggests that capsaicin may reduce body weight and fat accumulation in high fat diet-induced obese rats. These effects may be mediated, at least partially, by the upregulation of UCP2 gene expression and its ability to inhibit GPDH activity.

• 생명과학회지
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• 제29권8호
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• pp.922-940
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• 2019

비만은 에너지 섭취와 소비의 불균형으로 인해 유발되는 비정상적인 지방 축적으로, 근래에 다양한 만성질환을 초래하는 주요 국제 보건 문제로 부상하였다. 이러한 이유로, 비만 문제에 대한 여러 해결책들이 제시되고 있다. 에너지를 저장하며 내분비 작용을 하는 백색 지방과 달리 열을 생성하여 에너지를 발산하는 두 종류의 지방조직인 갈색 지방과 베이지색 지방이 성인에 존재하며 외부 자극에 의해 유도될 수 있다는 것이 밝혀진 이래로, 이들은 비만 치료의 유망한 표적으로서 각광받고 있다. 이러한 외부 자극 중, 인간 장관계에서 인간과 공존하는 장내 미생물총은 다양한 대사 작용에 참여하며, 이를 조절하는 것이 여러 대사 질환의 치료에 유력한 작용을 할 것으로 보인다. 따라서, 다양한 연구에서 항비만 치료가 장내 미생물 환경 전환이나 갈색 지방 조직 활성화에 미치는 영향에 초점을 맞추고 있다. 본 총설에서는 비만과 체중 증가, 대사 질환을 해소하는 것으로 알려진 자극과, 장내 미생물총의 변화나 갈색지방의 활성화를 야기하는 자극과, 이 자극들과 장내 미생물총의 조작, 지방조직의 갈색화 사이에서 알려져 있거나 있을 수 있는 상관관계를 중점적으로 다루고자 한다.

• Journal of Acupuncture Research
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• 제24권1호
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• pp.165-177
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• 2007

Objectives : This study anus to investigate the effects of Rosa Rugosae Radix (RU) herbal acupuncture on the metabolic syndrome in high-fat diet-fed mice. Methods : The experimental groups were fed with high-fat diet (HFD) for 8 weeks to induce metabolic syndrome. During the induction of metabolic syndrome, RU herbal acupuncture at a dosage of 50 mg/kg was carried out on the point of Sinsu(BL23) every day to measure the body weight, feed efficiency, blood glucose levels, insulin resistance index, lipid levels, blood pressure, and weight of liver and adipose tissues (brown adipose tissue from interscapular fat and white adipose tissue from epididymal fat). And after five weeks' induction of metabolic syndrome, RU herbal acupuncture was also performed for 6 weeks to measure the body weight and blood glucose levels. Results: 1. RU herbal acupuncture inhibited increasing body weight and blood glucose levels, with improved insulin resistance. 2. RU herbal acupuncture inhibited increasing levels of total cholesterol, LDL-cholesterol and free fatty acid, while increased HDL-cholesterol levels. 3. RU herbal acupuncture activated anti-hypertensive action. 4. RU herbal acupuncture inhibited increasing weight of white adipose tissues, but not in brown adipose tissues and liver. 5. RU herbal acupuncture lowered blood glucose levels and inhibited increasing body weight in metabolic syndrome-induced ICR mice. Conclusion : Rosa Rugosae Radix (RU) herbal acupuncture showed effectiveeness in prevention and management of metabolic syndrome in clinical application.

• 한방재활의학과학회지
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• 제21권1호
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• pp.1-22
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• 2011

Objectives : This study was undertaken to verify the effects of Wolbigachul-tang1(WBCEx1) on obesity using high fat diet-induced male mice and to investigate the molecular mechanisms involved. Methods : 8-week old C57BL/6 mice were divided into 5 groups; lean control, obese control, WBCEx1, 2, 3. After mice were treated with WBCEx1(water extract), 2(30% ethanol extract), 3(water extract; Ephedra sinica Stapf., Gypsum fibrosum) for 12 weeks, body weight gain, feeding efficiency ratio, plasma lipid and glucose metabolism, the messenger RNA(mRNA) expression of peroxisome proliferator activated receptor(PPAR)$\alpha$ target genes were measured. In addition, $PPAR{\alpha}$ target gene expression was examined in liver, white adipose tissue and skeletal muscle. Results : 1. WBCEx1-treated mice had significantly lower body weight gain and feeding efficiency ratio. 2. Consistent with the effects on body weight gain, WBCEx1 decreased the weights of epididymal and retroperitoneal white adipose tissue, inguinal subcutaneous adipose tissue, and brown adipose tissue. 3. WBCEx1 significantly decreased plasma triglyceride and total cholesterol levels. 4. The size of adipocytes were significantly decreased by WBCEx1, whereas the adipocyte number per unit area was increased. Hepatic lipid accumulation was decreased by WBCEx1. 5. WBCEx1 did not affect the mRNA expression of $PPAR{\alpha}$ target genes in liver, adipose tissue, and skeletal muscle. 6. Plasma asparate aminotransferase(AST), alanine aminotransferase(ALT), blood urea nitrogen(BUN) and creatine concentrations were in the physiological range. Liver and kidney weights were significantly lower following WBCEx treatment compared with obese controls, indicating that WBCEx does not show any toxic effects on liver and kidney. Conclusions : These results suggest that WBCEx1-induced body weight reduction is associated with appetite control and mediated by a mechanism other than the activation of $PPAR{\alpha}$.