• BMB Reports
• /
• 제40권6호
• /
• pp.921-927
• /
• 2007

UCP2 and UCP3 are members of the uncoupling protein family, which may play roles in energy homeostasis. In order to determine the regulation of the predominant expression of UCP3 in skeletal muscle, the effects of differentiation and myogenic regulatory factors on the promoter activities of the mouse UCP2 and UCP3 genes were studied. Reporter plasmids, containing approximately 3 kb of the 5'-upstream region of the mouse UCP2 and UCP3 genes, were transfected into C2C12 myoblasts, which were then induced to differentiate. Differentiation positively induced the reporter expression about 20-fold via the UCP3 promoter, but by only 2-fold via the UCP2 promoter. C2C12 myoblasts were cotransfected with expression vectors for myogenin and/or MyoD as well as reporter constructs. The simultaneous expression of myogenin and MyoD caused an additional 20-fold increase in the reporter expression via the UCP3 promoter, but only a weak effect via the UCP2 promoter. In L6 myoblasts, only MyoD activated the UCP3 promoter, but in 3T3-L1 cells neither factor activated the UCP3 promoter, indicating that additional cofactors are required, which are present only in C2C12 myoblasts. The expression of UCP2 and UCP3 is differentially regulated during muscle differentiation due to the different responsiveness of their promoter regions to myogenin and MyoD.

• 한국해양생명과학회지
• /
• 제8권2호
• /
• pp.186-189
• /
• 2023

Uncoupling protein 1 (UCP1) is a unique mitochondrial membranous protein expressed in brown adipose tissue (BAT) in mammals. While its expression in response to cold temperatures and adipogenic inducers is well-characterized in mammals and human infants, the molecular characterization and expression of UCP1 in fish remain unexplored. To address this gap, we analyzed UCP1 expression in response to adipogenic inducers in a fish cell line, rainbow trout gonadal cells (RTG-2), and compared it with UCP1 expression in three mammalian preadipocytes, 3T3-L1, T37i, and WT1 exposed to the Peroxisome proliferator-activated receptor gamma (PPARγ) agonists, rosiglitazone (Rosi). In mammalian preadipocytes, UCP1 protein was highly expressed by Rosi, with an induction of adipogenesis observed in a time-dependent manner. This suggests that UCP1 plays a significant role in adipogenesis in mammals. However, RTG-2 cells showed no response to adipogenic inducers and exhibited only marginal expressions of UCP1. These results imply that RTG-2 cells may lack crucial responsive mechanisms to adipogenic signals or that the adipogenic response is regulated by other mechanisms. Further studies are needed to confirm these phenomena in fish preadipocytes when an appropriate cell line is established in future research.

• BMB Reports
• /
• 제54권8호
• /
• pp.419-424
• /
• 2021

Cold-induced norepinephrine activates β3-adrenergic receptors (β3-AR) to stimulate the kinase cascade and cAMP-response element-binding protein, leading to the induction of thermogenic gene expression including uncoupling protein 1 (Ucp1). Here, we showed that stimulation of the β3-AR by its agonists isoproterenol and CL316,243 in adipocytes increased the expression of Ucp1 and Heme Oxygenase 1 (Hmox1), the principal Nrf2 target gene, suggesting the functional interaction of Nrf2 with β3-AR signaling. The activation of Nrf2 by tert-butylhydroquinone and reactive oxygen species (ROS) production by glucose oxidase induced both Ucp1 and Hmox1 expression. The increased expression of Ucp1 and Hmox1 was significantly reduced in the presence of a Nrf2 chemical inhibitor or in Nrf2-deleted (knockout) adipocytes. Furthermore, Nrf2 directly activated the Ucp1 promoter, and this required DNA regions located at -3.7 and -2.0 kb of the transcription start site. The CL316,243-induced Ucp1 expression in adipocytes and oxygen consumption in obese mice were partly compromised in the absence of Nrf2 expression. These data provide additional insight into the role of Nrf2 in β3-AR-mediated Ucp1 expression and energy expenditure, further highlighting the utility of Nrf2-mediated thermogenic stimulation as a therapeutic approach to diet-induced obesity.

• Asian-Australasian Journal of Animal Sciences
• /
• 제32권2호
• /
• pp.170-175
• /
• 2019

Objective: Uncoupling protein 3 gene (UCP3) is a candidate gene associated with the meat quality of pigs. The aim of this study was to explore the regulation mechanism of UCP3 expression and provide a theoretical basis for the research of the function of porcine UCP3 gene in meat quality. Methods: Bisulfite sequencing polymerase chain reaction (PCR) and quantitative real-time PCR (Q-PCR) were used to analyze the methylation of UCP3 5′-flanking region and UCP3 mRNA expression in the adipose tissue or skeletal muscle of three pig breeds at different ages (1, 90, 210-day-old Putian Black pig; 90-day-old Duroc; and 90-day-old Dupu). Results: Results showed that two cytosine-guanine dinucleotide (CpG) islands are present in the promoter region of porcine UCP3 gene. The second CpG island located in the core promoter region contained 9 CpG sites. The methylation level of CpG island 2 was lower in the adipose tissue and skeletal muscle of 90-day-old Putian Black pigs compared with 1-day-old and 210-day-old Putian Black pigs, and the difference also existed in the skeletal muscle among the three 90-day-old pig breeds. Furthermore, the obvious changing difference of UCP3 mRNA expression was observed in the skeletal muscle of different groups. However, the difference of methylation status and expression level of UCP3 gene was not significant in the adipose tissue. Conclusion: Our data indicate that UCP3 mRNA expression level was associated with the methylation status of UCP3 promoter in the skeletal muscle of pigs.

• Asian-Australasian Journal of Animal Sciences
• /
• 제18권11호
• /
• pp.1552-1556
• /
• 2005

The UCPs are members of the mitochondrial inner membrane transporter family, present in the mitochondrial inner membrane. Their main function is increasing the energy expenditure via diminishing the resulting production of ATP from mitochondrial oxidative phosphorylation instead of yielding dissipative heat. They are associated with the metabolism of fat and regulation of energy expenditure. The UCP gene can be viewed as the candidate gene for chicken fatness. In the present study, RT-PCR and Northern Blot methods were developed to investigate the expression of the UCP gene in ten tissues including heart, liver, spleen, lung, kidney, gizzard, intestine, brain, breast muscle and abdominal fat of chicken. The results of both RT-PCR and Northern Blot methods showed that the UCP gene expressed specific in breast muscle. The expression levels of UCP gene in breast muscles from egg-type and meat-type chickens of hatching, 2, 4, 6 and 8 wk of age were detected by RT-PCR assay and results showed that the expression levels of UCP gene were related to breeds. Expression level of UCP gene in layers was higher than that in broilers at various weeks of age except at 6 wk. The UCP gene's expression was higher at 6 wk and had no significant difference among other weeks of age in broilers; in layers the expression level of UCP gene had no significant difference among weeks of age. The experiment results also showed that insulin could increase the expression level of UCP gene by 40% compared with control group.

• 생명과학회지
• /
• 제19권2호
• /
• pp.213-218
• /
• 2009

본 연구에서는 F344계 흰쥐를 대상으로 8주간 저강도 운동군과 고강도 운동군으로 나누어 수영운동을 실시하여, 갈색지방조직 내 UCP-1과 UCP-3mRNA 발현을 관찰하고 혈당 및 인슐린 수준이 어떠한 변화를 나타내는지 알아보았다. 그 결과 저강도 수영을 실시한 그룹이 대조군과 고강도 운동그룹보다 갈색지방조직 내 UCP-1과 UCP-3 mRNA 발현이 증가되는 것을 관찰하였으며, 고강도 수영군에서 대조군 보다 인슐린 수준이 낮게 나타났으나 혈당에서는 유의한차가 나타나지 않았다. 하지만 저강도 수영군에서 대조군보다 혈당 및 인슐린 수준이 유의하게 감소하는 것을 관찰하였다. 이러한 결과는 저강도 수영운동이 갈색지방조직 내 UCP-1과 UCP-3mRNA 발현을 증가시키고, 당대사를 활성화하여 인슐린민감도를 개선시킬 수 있음을 보여주는 결과이다.

• Journal of Nutrition and Health
• /
• 제35권9호
• /
• pp.903-911
• /
• 2002

The effects of dietary levan, high-molecular-weight $\beta$-2,6-linked fructose polymer, on adiposity, serum leptin and UCP expression in rats fed high fat diet were studied. The adipose tissue hormone, leptin has been proposed to be involved in the regulation of food intake and energy expenditure. Uncoupling protein (UCP), a mitochondrial protein that uncouples the respiratory chain from oxidative phosphorylation, generates heat instead of ATP, thereby increase energy expenditure. To determine whether the dietary levan may have the anti-obesity effect, 4 wk old Sprague Dawley male rats fed high fat diet for 6 wks to induce obesity, and subsequently fed one of three diets for further 6 wks: 1) high fat (40% of calories) diet without levan 2) with 3% (w/w) levan 3) with 5% levan. For the comparison, control group fed AIN-76A diet. Visceral and peritoneal fat masses were lower in high fat diet with levan groups compared to high fat diet group. The effect of levan was dose-dependent. Adipocyte size was significantly reduced in the levan diet groups compared to the no levan diet group. Serum cholesterol level was not affected by levan containing diet, while the serum HDL cholesterol level was higher in leven diet groups. In addition, serum triglyceride level was markedly reduced by levan containing diet, thus lower than that of control group. Serum leptin was reduced by levan containing diet and lower in 5% levan group compared to 3% levan group (p < 0.001), as a result, serum leptin and insulin levels of 5% levan group were reduced to level of control group. Futhermore, the serum leptin level reflected the adiposity. The expression of UCP 1, and UCP 2 in brown adipose tissue was up-regulated by levan containing diet. In conclusions, levan containing diet reduced adiposity and serum triglyceride but increased UCP expression in the obese rats fed high fat diet. (Korean J Nutrition 35(9) : 903~911, 2002)

• 한국식품영양과학회지
• /
• 제31권5호
• /
• pp.788-795
• /
• 2002

본 연구는 프락토즈 중합체인 레반의 지질 감소 효과와 비만 유전자인 UCP를 통한 에너지 대사에 미치는 효과를 살펴보기 위하여 성장기 6주간 AIN-76A diet로 사육한 흰쥐에게 레반을 식이 섭취량의 1%, 2%로 5주간 경구투여하여, 혈중 지질 수준과 체지방 형성 및 혈중 인슬린, 렙틴 농도와 갈색 지방 조직, 백색지방 조직, 골격 근육, 시상하부에서 의 UCP mRNA 발현량 변화를 관찰하였다. 연구 결과를 종합해 보면 다음과 같다. 1) 레반군에서 혈청 중성지방과 총 콜레스테롤은 감소하고 HDL 콜레스테롤 수준은 영향을 미치지 않아 1%와 2% 레반 공급이 지질 대사를 개선시킬 수 있음을 보여주었다. 2) 1%와 2% 레반군에서 내장 지방 무게가 감소하여 적은 양의 레반 공급으로 체지방 축적이 억제될 수 있음을 보여주었다. 3) 갈색 지방 조직과 부고환 지방, 복막 지방 무게는 그룹간 차이가 나타나지 않았다. 4) 혈청 인슬린 농도는 1% 레반군에서, 혈청 렙틴 농도는 1% 레반군, 2% 레반군에서 대조군에 비해 감소하는 경향을 나타내었으나 통계적 유의성은 나타나지 않았다. 5) 1%와 2% 레반 공급에 의하여 갈색 지방 조직과 골격근육, 시상하부에서의 UCP mRNA발현량에는 변화가 없었다. 6) 백색 지방 조직의 UCP 2 mRNA 발현량이 레반 공급에 의해 증가하여 1%와 2%레반 공급에 의해 에너지 소비율이 증가할 수 있음이 나타났다 결론적으로 저농도의 1%와 1% 액상 레반 공급은 총 식이의 ,3%～5% 레반 공급과 비교하여 혈중 총 콜레스테롤과 중성 지방 감소 효과에는 차이가 있으나 UCP 발현 증가에 미치는 영향은 적은 것으로 보인다. 그러나 저농도의 1～2% 액상 레반 공급으로 지질 대사를 개선하고 체지방 축적을 어느 정도 억제하는 효과를 나타냄을 알 수 있으며 이에 관한 임상 연구로 레반의 고지혈증과 비만을 조절하는 기능성 식품 소재로서의 가능성 검색이 요망된다.

• BMB Reports
• /
• 제39권4호
• /
• pp.346-354
• /
• 2006

The full-length cDNA of grass carp (Ctenopharyngodon idellus) and silver carp (Hypophthalmichthys molitrix) uncoupling protein 2 (UCP2) was obtained from liver. The grass carp UCP2 cDNA was determined to be 1152 bp in length with an open reading frame that encodes 310 amino acids. Five introns (Intron 3, 4, 5, 6 and 7) in the translated region, and partial sequence of Intron 2 in the untranslated region of grass carp UCP2 gene were also obtained. Gene structure comparison between grass carp and mammalian (human and mouse) UCP2 gene shows that, the UCP2 gene structure of grass carp is much similar to that of human and mouse. Partial UCP2 cDNA sequences of bighead carp (Aristichthys nobilis) and mud carp (Cirrhinus molitorella), were further determined. Together with the common carp (Cyprinus carpio) UCP2 sequence from GenBank (AJ243486), multiple alignment result shows that the nucleotide and amino acid sequences of the UCP2 gene, were highly conserved among the five major Chinese carps that belong to four subfamilies. Using beta-actin as control, the ratio UCP2/beta-actin mRNA (%) was determined to be $149.4{\pm}15.6$ (common carp), $127.4{\pm}22.1$ (mud carp), $96.7{\pm}12.7$ (silver carp), $94.1{\pm}26.8$ (bighead carp) and $63.7{\pm}16.2$ (grass carp). The relative liver UCP2 expression of the five major Chinese carps, shows a close relationship with their food habit: benthos and detrituseating fish (common carp and mud carp) > planktivorious fish (silver carp and bighead carp) > herbivorious fish (grass carp). We suggest that liver UCP2 might be important for Chinese carps to detoxify cyanotoxins and bacteria in debris and plankton food.

• 생명과학회지
• /
• 제19권1호
• /
• pp.15-20
• /
• 2009

Uncoupling protein 3 (UCP3)는 골격근에서 주로 발현되는 미토콘드리아 단백질이다. 생체의 대사기능에 관여할 것으로 알려져 있지만, 아직 그 역할에 대하여 깊이 연구되어 있지 않다. 최근에 고지혈증 치료제인 페노파이브레이트를 처치한 쥐의 간에서는 UCP3가 새로이 발현 유도된다는 것이 알려졌으며, 본 연구자들은 새로이 발현되는 UCP3가 비만쥐의 지방조직올 감소시키며, 인슐린 감수성을 증가시킨다는 보고를 하였다. 본 연구에서는 이러한 새로이 발현되는 UCP3의 시간에 따른 발현 양상과 대사 기능의 연관 관계를 규명하고자 하였다. 8주령 흰쥐를 두 군으로 나누어, 한 군은 고지방 식이를 실시하고(HF군), 다른 군은 고지방 식이와 페노파이브레이트(HFF군)를 함께 복용토록 하였다. 10주 동안 식이와 약물을 처리하면서, 1, 3, 6주에 간조직올 분석하였으며, 매주 먹이량, 체중, 체온을 측정하였다. 페노파이브레이트에 의하여 간에서 새로이 발현되는 UCP3는 2주부터 시작하여 3, 6주에 아주 높은 발현 양상을 보였다. 두 군 간의 먹이량의 차이는 없는 반면, 페노파이브레이트 처리군에서 6 주부터 시작하여 체중증가가 억제되며, 오히려 감소되는 경향을 보였다. 체온은 페노파이브레이트 처리군에서 6주부터 상승하기 시작하여, UCP3의 발현에 의한 간에서의 upcoupling 현상에 따른 발열현상으로 추측할 수 있다. 이상의 결과들로 유추해 볼 때, UCP3 발현이 3-6주부터 많은 양이 생성되어 생체의 대사 기능에 영향을 미치며, 이러한 시기와 연관되어 체중, 체온의 변화와 관련이 있는 것으로 생각한다.