1
|
Guo H, Yu X, Liu Z, Li J, Ye J, Zha Z. Deltamethrin transformation by Bacillus thuringiensis and the associated metabolic pathways. ENVIRONMENT INTERNATIONAL 2020; 145:106167. [PMID: 33035892 DOI: 10.1016/j.envint.2020.106167] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/08/2020] [Accepted: 09/25/2020] [Indexed: 05/22/2023]
Abstract
The biological toxicity of deltamethrin at molecular level has been investigated, whereas, the proteome responsive mechanisms of cells under deltamethrin stress at the phylogenetic level are not clear. The proteome expression, transformation-related pathway and regulatory network of Bacillus thuringiensis during the process of deltamethrin transformation were explored using proteomics and metabolomics approaches in the present study. The results showed that deltamethrin was effectively removed by B. thuringiensis within 48 h. The stress responses of B. thuringiensis were activated to resist deltamethrin stress, with significant differential expression of proteins that were primarily involved in the synthesis of DNA and shock proteins, endospore formation, carbon metabolism. The expression patterns of ribosomal proteins confirmed that the transcription and translation of DNA, and biosynthesis of heat shock proteins were inhibited as deltamethrin transformation. The synthesis of oxaloacetate and acetyl-CoA were also hindered, resulting in downregulated expression of carbohydrate metabolism, TCA cycle and energy metabolism. Meanwhile, endospore formation and germination were promoted to resist oxidative stress induced by deltamethrin. These findings imparted novel insight to elucidate underlying stress response mechanisms of the organism under target contaminants stress, and the interaction between deltamethrin transformation and cellular metabolism at the pathway and network levels.
Collapse
Affiliation(s)
- Huiying Guo
- Institute of Orthopedic Diseases and Department of Bone and Joint Surgery, The First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - Xiaolong Yu
- Guangdong Provincial Key Laboratory of Petrochemical Pollution Processes and Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, China
| | - Ziyi Liu
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Jieruo Li
- Institute of Orthopedic Diseases and Department of Bone and Joint Surgery, The First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - Jinshao Ye
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China.
| | - Zhengang Zha
- Institute of Orthopedic Diseases and Department of Bone and Joint Surgery, The First Affiliated Hospital, Jinan University, Guangzhou 510630, China.
| |
Collapse
|
2
|
Prognostic Value of the Overexpression of Fatty Acid Metabolism-Related Enzymes in Squamous Cell Carcinoma of the Head and Neck. Int J Mol Sci 2020; 21:ijms21186851. [PMID: 32961983 PMCID: PMC7559281 DOI: 10.3390/ijms21186851] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 09/11/2020] [Accepted: 09/16/2020] [Indexed: 02/07/2023] Open
Abstract
Reprogramming of cellular energy metabolism, such as lipid metabolism, is a hallmark of squamous cell carcinoma of the head and neck (SCCHN). However, whether protein expression related to fatty acid oxidation (FAO) affects survival in SCCHN remains unclear. We aimed to investigate FAO-related enzyme expression and determine its correlation with clinicopathological variables in SCCHN patients. Immunohistochemical analysis (IHC) of FAO-related protein expression, including carnitine palmitoyltransferase 1 (CPT1), the acyl-CoA dehydrogenase family, and fatty acid synthase (FAS), was performed using tissue microarrays from 102 resected SCCHN tumors. Expressions were categorized according to IHC scores, and the statistical association with clinicopathological factors was determined. Moderate-to-high expression of long-chain acyl-CoA dehydrogenase (LCAD) had a protective role against cancer-related death (adjusted hazard ratio (HR), 0.2; 95% confidence interval (CI), 0.05–0.87) after covariate adjustment. Age and clinical stage remained independent predictors of survival (adjusted HR, 1.75; 95% CI, 1.22–2.49 for age; adjusted HR, 14.33; 95% CI, 1.89–108.60 for stage III/IV disease). Overexpression of medium-chain acyl-CoA dehydrogenase and FAS correlated with advanced tumor stage (T3/T4); however, none of these factors were independent predictors of survival. Several FAO-related enzymes were upregulated and LCAD overexpression had a protective effect on overall survival in advanced SCCHN patients. FAO-related-enzyme expression might have a prognostic impact on survival outcomes in SCCHN.
Collapse
|
3
|
Ning Q, Wang Y, Zhang Y, Shen G, Xie Z, Pang J. Nuciferine Prevents Hepatic Steatosis by Regulating Lipid Metabolismin Diabetic Rat Model. Open Life Sci 2019; 14:699-706. [PMID: 33817209 PMCID: PMC7874802 DOI: 10.1515/biol-2019-0079] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 10/21/2019] [Indexed: 12/13/2022] Open
Abstract
Objective This study investigatesthe nuciferine capacity to regulate the liver’s lipid metabolism regarding steatosis and injury in STZ-induced diabetic rats. Materials and Methods The rats were randomly divided into groups control, diabetic and nuciferine 200 mg/kg/ day treatment. After 4 days of STZ injection, the nuciferine group was treated and administered via oral gavages for 4 weeks. At the end of experiment, blood, liver, myocardial and muscular samples were collected. Results Nuciferine-treated significantly increased the body weight from 339.4g to 367.8g, but significantly decreased the food and water intake compared with diabetic rats. Also, the nuciferine-treated rats had significantly decreased TC, TG, and FFAs in the liver compared with the diabetic group, especially the serum markers of blood glucose. These were associated with the gene expression related to lipogenesis which was significantly down-regulated; the gene expression involved in lipolysis and fatty acid β-oxidation was significantly up-regulated. Discussion and Conclusion The data provide evidence that nuciferine supplementation could protect the liver by regulating lipid metabolism gene expression resulting in decreasing the steatosis and injury in diabetic rat. Thus, nuciferine could be developed as a diabetic adjuvant food additive in future.
Collapse
Affiliation(s)
- Qian Ning
- Jinshan College of Fujian Agriculture and Forestry University, Fujian Province, 350001, P. R. China
| | - Yang Wang
- Jinshan College of Fujian Agriculture and Forestry University, Fujian Province, 350001, P. R. China
| | - Yi Zhang
- Jinshan College of Fujian Agriculture and Forestry University, Fujian Province, 350001, P. R. China
| | - Guozhi Shen
- Jinshan College of Fujian Agriculture and Forestry University, Fujian Province, 350001, P. R. China
| | - Zhenglu Xie
- Jinshan College of Fujian Agriculture and Forestry University, Fujian Province, 350001, P. R. China.,Collaborative Innovation Center of Animal Health and Food Safety Application Technology in Fujian, Fujian Vocational College of Agriculture, Fuzhou City, Fujian Province, 350002, P.R. China
| | - Jie Pang
- College of Food Science, Fujian Agriculture and Forestry University, Fujian Province, 350001, P. R. China
| |
Collapse
|
4
|
Lim SM, Lee HS, Jung JI, Kim SM, Kim NY, Seo TS, Bae JS, Kim EJ. Cyanidin-3- O-galactoside-enriched Aronia m elanocarpa extract attenuates weight gain and adipogenic pathways in high-fat diet-induced obese C57BL/6 mice. Nutrients 2019; 11:nu11051190. [PMID: 31137884 PMCID: PMC6566507 DOI: 10.3390/nu11051190] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 05/16/2019] [Accepted: 05/23/2019] [Indexed: 02/07/2023] Open
Abstract
Aronia melanocarpa are a rich source of anthocyanins that have received considerable interest for their relations to human health. In this study, the anti-adipogenic effect of cyanidin-3-O-galactoside-enriched Aronia melanocarpa extract (AM-Ex) and its underlying mechanisms were investigated in an in vivo system. Five-week-old male C57BL/6N mice were randomly divided into five groups for 8-week feeding with a control diet (CD), a high-fat diet (HFD), or a HFD with 50 (AM-Ex 50), 100 (AM-Ex 100), or 200 AM-Ex (AM-Ex 200) mg/kg body weight/day. HFD-fed mice showed a significant increase in body weight compared to the CD group, and AM-Ex dose-dependently inhibited this weight gain. AM-Ex significantly reduced the food intake and the weight of white fat tissue, including epididymal fat, retroperitoneal fat, mesenteric fat, and inguinal fat. Treatment with AM-Ex (50 to 200 mg/kg) reduced serum levels of leptin, insulin, triglyceride, total cholesterol, and low density lipoprotein (LDL)-cholesterol. Real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed that AM-Ex suppressed adipogenesis by decreasing CCAAT/enhancer binding protein α, peroxisome proliferator-activated receptor γ, sterol regulatory element-binding protein-1c, peroxisome proliferator-activated receptor gamma coactivator-1α, acetyl-CoA carboxylase 1, ATP-citrate lyase, fatty acid synthase, and adipocyte protein 2 messenger RNA (mRNA) expressions. These results suggest that AM-Ex is potentially beneficial for the suppression of HFD-induced obesity by modulating multiple pathways associated with adipogenesis and food intake.
Collapse
Affiliation(s)
- Su-Min Lim
- Center for Efficacy Assessment and Development of Functional Foods and Drugs, Hallym University, Chuncheon, Gangwon 24252, Korea.
| | - Hyun Sook Lee
- Department of Food Science & Nutrition, Dongseo University, Busan 47011, Korea.
| | - Jae In Jung
- Center for Efficacy Assessment and Development of Functional Foods and Drugs, Hallym University, Chuncheon, Gangwon 24252, Korea.
| | - So Mi Kim
- Center for Efficacy Assessment and Development of Functional Foods and Drugs, Hallym University, Chuncheon, Gangwon 24252, Korea.
| | - Nam Young Kim
- R&D center, Wellfine Co., Ltd, Chuncheon, Gangwon 24232, Korea.
| | - Tae Su Seo
- R&D center, Wellfine Co., Ltd, Chuncheon, Gangwon 24232, Korea.
| | - Jung-Shik Bae
- R&D center, Wellfine Co., Ltd, Chuncheon, Gangwon 24232, Korea.
| | - Eun Ji Kim
- Center for Efficacy Assessment and Development of Functional Foods and Drugs, Hallym University, Chuncheon, Gangwon 24252, Korea.
| |
Collapse
|
5
|
Cheon SY, Chung KS, Roh SS, Cha YY, An HJ. Bee Venom Suppresses the Differentiation of Preadipocytes and High Fat Diet-Induced Obesity by Inhibiting Adipogenesis. Toxins (Basel) 2017; 10:toxins10010009. [PMID: 29295544 PMCID: PMC5793096 DOI: 10.3390/toxins10010009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 12/21/2017] [Accepted: 12/21/2017] [Indexed: 02/07/2023] Open
Abstract
Bee venom (BV) has been widely used in the treatment of certain immune-related diseases. It has been used for pain relief and in the treatment of chronic inflammatory diseases. Despite its extensive use, there is little documented evidence to demonstrate its medicinal utility against obesity. In this study, we demonstrated the inhibitory effects of BV on adipocyte differentiation in 3T3-L1 cells and on a high fat diet (HFD)-induced obesity mouse model through the inhibition of adipogenesis. BV inhibited lipid accumulation, visualized by Oil Red O staining, without cytotoxicity in the 3T3-L1 cells. Male C57BL/6 mice were fed either a HFD or a control diet for 8 weeks, and BV (0.1 mg/kg or 1 mg/kg) or saline was injected during the last 4 weeks. BV-treated mice showed a reduced body weight gain. BV was shown to inhibit adipogenesis by downregulating the expression of the transcription factors CCAAT/enhancer-binding proteins (C/EBPs) and the peroxisome proliferator-activated receptor gamma (PPARγ), using RT-qPCR and Western blotting. BV induced the phosphorylation of AMP-activated kinase (AMPK) and acetyl-CoA carboxylase (ACC) in the cell line and in obese mice. These findings demonstrate that BV mediates anti-obesity/differentiation effects by suppressing obesity-related transcription factors.
Collapse
Affiliation(s)
- Se-Yun Cheon
- Department of Pharmacology, College of Korean Medicine, Sang-ji University, Wonju-si, Gangwon-do 26339, Korea.
| | - Kyung-Sook Chung
- Catholic Precision Medicine Research Center, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul 06591, Korea.
| | - Seong-Soo Roh
- Department of Herbology, College of Korean Medicine, Daegu Hanny University, Suseong-gu, Deagu 42158, Korea.
| | - Yun-Yeop Cha
- Department of Rehabilitation Medicine of Korean Medicine and Neuropsychiatry, College of Korean Medicine, Sang-ji University, Wonju-si, Gangwon-do 26339, Korea.
| | - Hyo-Jin An
- Department of Pharmacology, College of Korean Medicine, Sang-ji University, Wonju-si, Gangwon-do 26339, Korea.
| |
Collapse
|
6
|
Biotin augments acetyl CoA carboxylase 2 gene expression in the hypothalamus, leading to the suppression of food intake in mice. Biochem Biophys Res Commun 2016; 476:134-9. [DOI: 10.1016/j.bbrc.2016.04.152] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 04/27/2016] [Indexed: 01/19/2023]
|
7
|
Ilavenil S, Kim DH, Valan Arasu M, Srigopalram S, Sivanesan R, Choi KC. Phenyllactic Acid from Lactobacillus plantarum PromotesAdipogenic Activity in 3T3-L1 Adipocyte via Up-Regulationof PPAR-γ2. Molecules 2015; 20:15359-73. [PMID: 26305241 PMCID: PMC6332376 DOI: 10.3390/molecules200815359] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 08/17/2015] [Accepted: 08/19/2015] [Indexed: 11/16/2022] Open
Abstract
Synthetic drugs are commonly used to cure various human ailments at present. However, the uses of synthetic drugs are strictly regulated because of their adverse effects. Thus, naturally occurring molecules may be more suitable for curing disease without unfavorable effects. Therefore, we investigated phenyllactic acid (PLA) from Lactobacillus plantarum with respect to its effects on adipogenic genes and their protein expression in 3T3-L1 pre-adipocytes by qPCR and western blot techniques. PLA enhanced differentiation and lipid accumulation in 3T3-L1 cells at the concentrations of 25, 50, and 100 μM. Maximum differentiation and lipid accumulation were observed at a concentration of 100 μM of PLA, as compared with control adipocytes (p < 0.05). The mRNA and protein expression of PPAR-γ2, C/EBP-α, adiponectin, fatty acid synthase (FAS), and SREBP-1 were increased by PLA treatment as compared with control adipocytes (p < 0.05). PLA stimulates PPAR-γ mRNA expression in a concentration dependent manner, but this expression was lesser than agonist (2.83 ± 0.014 fold) of PPAR-γ2. Moreover, PLA supplementation enhances glucose uptake in 3T3-L1 pre-adipocytes (11.81 ± 0.17 mM) compared to control adipocytes, but this glucose uptake was lesser than that induced by troglitazone (13.75 ± 0.95 mM) and insulin treatment (15.49 ± 0.20 mM). Hence, we conclude that PLA treatment enhances adipocyte differentiation and glucose uptake via activation of PPAR-γ2, and PLA may thus be the potential candidate for preventing Type 2 Diabetes Mellitus (T2DM).
Collapse
Affiliation(s)
- Soundharrajan Ilavenil
- Grassland and Forage Division, National Institute of Animal Science, RDA, Seonghwan-Eup, Cheonan-Si, Chungnam 330801, Korea.
| | - Da Hye Kim
- The United Graduate School of Agricultural Sciences, Tottori University, Tottori-Shi 6808553, Japan.
| | - Mariadhas Valan Arasu
- Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia.
| | - Srisesharam Srigopalram
- Grassland and Forage Division, National Institute of Animal Science, RDA, Seonghwan-Eup, Cheonan-Si, Chungnam 330801, Korea.
| | | | - Ki Choon Choi
- Grassland and Forage Division, National Institute of Animal Science, RDA, Seonghwan-Eup, Cheonan-Si, Chungnam 330801, Korea.
| |
Collapse
|
8
|
Aoki H, Kimura K, Igarashi K, Takenaka A. Soy Protein Suppresses Gene Expression of Acetyl-CoA Carboxylase Alpha from Promoter PI in Rat Liver. Biosci Biotechnol Biochem 2014; 70:843-9. [PMID: 16636450 DOI: 10.1271/bbb.70.843] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Dietary soy protein isolate (SPI) reduces hepatic lipogenesis by suppressing gene expression of lipogenic enzymes, including acetyl-CoA carboxylase (ACC). In order to elucidate the mechanism of this regulation, the effect of dietary SPI on promoter (PI and PII) specific gene expression of ACC alpha was investigated. Rats were fed experimental diets containing SPI or casein as a nitrogen source. SPI feeding decreased the hepatic contents of total ACC mRNA as well as triglyceride (TG) content, but dietary SPI affected the amount of sterol-regulatory element binding protein (SREBP)-1 mRNA and protein very little. The amount of ACC mRNA transcribed from PII promoter containing SRE was not significantly affected by dietary protein, while a significant decrease in PI-generated ACC mRNA content was observed in rats fed the SPI diet. These data suggest that SPI feeding decreased the hepatic contents of ACC alpha mRNA mainly by regulating PI promoter via a nuclear factor(s) other than SREBP-1.
Collapse
Affiliation(s)
- Hisa Aoki
- Course of the Science of Bioresources, The United Graduate School of Agricultural Sciences, Iwate University, Iwate, Japan
| | | | | | | |
Collapse
|
9
|
Flint DJ, Travers MT, Barber MC, Binart N, Kelly PA. Diet-induced obesity impairs mammary development and lactogenesis in murine mammary gland. Am J Physiol Endocrinol Metab 2005; 288:E1179-87. [PMID: 15671082 DOI: 10.1152/ajpendo.00433.2004] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have developed a mouse model of diet-induced obesity that shows numerous abnormalities relating to mammary gland function. Animals ate approximately 40% more calories when offered a high-fat diet and gained weight at three times the rate of controls. They exhibited reduced conception rates, increased peripartum pup mortality, and impaired lactogenesis. The impairment of lactogenesis involved lipid accumulation in the secretory epithelial cells indicative of an absence of copius milk secretion. Expression of mRNAs for beta-casein, whey acid protein, and alpha-lactalbumin were all decreased immediately postpartum but recovered as lactation was established over 2-3 days. Expression of acetyl-CoA carboxylase (ACC)-alpha mRNA was also decreased at parturition as was the total enzyme activity, although there was a compensatory increase in the proportion in the active state. By day 10 of lactation, the proportion of ACC in the active state was also decreased in obese animals, indicative of suppression of de novo fatty acid synthesis resulting from the supply of preformed fatty acids in the diet. Although obese animals consumed more calories in the nonpregnant and early pregnant states, they showed a marked depression in fat intake around day 9 of pregnancy before food intake recovered in later pregnancy. Food intake increased dramatically in both lean and obese animals during lactation although total calories consumed were identical in both groups. Thus, despite access to high-energy diets, the obese animals mobilized even more adipose tissue during lactation than their lean counterparts. Obese animals also exhibited marked abnormalities in alveolar development of the mammary gland, which may partially explain the delay in differentiation evident during lactogenesis.
Collapse
|
10
|
Barber MC, Price NT, Travers MT. Structure and regulation of acetyl-CoA carboxylase genes of metazoa. Biochim Biophys Acta Mol Cell Biol Lipids 2005; 1733:1-28. [PMID: 15749055 DOI: 10.1016/j.bbalip.2004.12.001] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2004] [Revised: 11/02/2004] [Accepted: 12/01/2004] [Indexed: 11/16/2022]
Abstract
Acetyl-CoA carboxylase (ACC) plays a fundamental role in fatty acid metabolism. The reaction product, malonyl-CoA, is both an intermediate in the de novo synthesis of long-chain fatty acids and also a substrate for distinct fatty acyl-CoA elongation enzymes. In metazoans, which have evolved energy storage tissues to fuel locomotion and to survive periods of starvation, energy charge sensing at the level of the individual cell plays a role in fuel selection and metabolic orchestration between tissues. In mammals, and probably other metazoans, ACC forms a component of an energy sensor with malonyl-CoA, acting as a signal to reciprocally control the mitochondrial transport step of long-chain fatty acid oxidation through the inhibition of carnitine palmitoyltransferase I (CPT I). To reflect this pivotal role in cell function, ACC is subject to complex regulation. Higher metazoan evolution is associated with the duplication of an ancestral ACC gene, and with organismal complexity, there is an increasing diversity of transcripts from the ACC paraloges with the potential for the existence of several isozymes. This review focuses on the structure of ACC genes and the putative individual roles of their gene products in fatty acid metabolism, taking an evolutionary viewpoint provided by data in genome databases.
Collapse
Affiliation(s)
- Michael C Barber
- Hannah Research Institute, Ayr, KA6 5HL, Scotland, United Kingdom.
| | | | | |
Collapse
|
11
|
Barber MC, Vallance AJ, Kennedy HT, Travers MT. Induction of transcripts derived from promoter III of the acetyl-CoA carboxylase-alpha gene in mammary gland is associated with recruitment of SREBP-1 to a region of the proximal promoter defined by a DNase I hypersensitive site. Biochem J 2003; 375:489-501. [PMID: 12871210 PMCID: PMC1223696 DOI: 10.1042/bj20030480] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2003] [Revised: 07/15/2003] [Accepted: 07/21/2003] [Indexed: 12/24/2022]
Abstract
ACC-alpha (acetyl-CoA carboxylase-alpha), a key regulator of fatty-acid metabolism, is encoded by mRNAs transcribed from three promoters, PI, PII and PIII, in the ovine genome. Enhanced expression of transcripts encoded by PIII in mammary gland during lactation is associated with alterations in chromatin structure that result in the detection of two DNase I hypersensitive sites, upstream of the start site. The most proximal site, located between -190 and -10, is characterized by the presence of an inverted-CCAAT box, C2 at -167, and E-boxes, E1 and E2, at -151 and -46. Deletion of these motifs, which bind nuclear factor-Y and upstream stimulatory factors respectively in gel-shift assays, attenuates the activity of luciferase reporter constructs in transfected cells. Chromatin immunoprecipitation demonstrated that these transcription factors were associated with PIII in vivo in both lactating and non-lactating mammary tissues. The basic helix-loop-helix-leucine zipper transcription factor, SREBP-1 (sterol-regulated-element-binding protein-1), transactivated PIII reporter constructs in transfected HC11 mammary cells, and this was dependent on the presence of E1, but not on C2 or E2. SREBP-1 was only associated with PIII in chromatin from lactating animals, which was coincident with a 4-fold increase in the precursor (125 kDa) form of SREBP-1 in microsomes and the appearance of the mature form (68 kDa) in the nucleus. SREBP-1 motifs are also present in the proximal region of PII, which is also induced in lactation. This indicates that SREBP-1 is a major developmental regulator of the programme of lipid synthesis de novo in the lactating mammary gland.
Collapse
|
12
|
Kim YJ, Yang JL, Kwun IS, Kim YH. Regulation of Acetyl-CoA Carboxylase Gene Expression by Hormones and Nutrients. Prev Nutr Food Sci 2003. [DOI: 10.3746/jfn.2003.8.1.061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
13
|
|
14
|
Travers MT, Vallance AJ, Gourlay HT, Gill CA, Klein I, Bottema CB, Barber MC. Promoter I of the ovine acetyl-CoA carboxylase-alpha gene: an E-box motif at -114 in the proximal promoter binds upstream stimulatory factor (USF)-1 and USF-2 and acts as an insulin-response sequence in differentiating adipocytes. Biochem J 2001; 359:273-84. [PMID: 11583573 PMCID: PMC1222145 DOI: 10.1042/0264-6021:3590273] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Acetyl-CoA carboxylase-alpha (ACC-alpha) plays a central role in co-ordinating de novo fatty acid synthesis in animal tissues. We have characterized the regulatory region of the ovine ACC-alpha gene. Three promoters, PI, PII and PIII, are dispersed throughout 50 kb of genomic DNA. Expression from PI is limited to adipose tissue and liver. Sequence comparison of the proximal promoters of ovine and mouse PIs demonstrates high nucleotide identity and that they are characterized by a TATA box at -29, C/EBP (CCAAT enhancer-binding protein)-binding motifs and multiple E-box motifs. A 4.3 kb ovine PI-luciferase reporter construct is insulin-responsive when transfected into differentiated ovine adipocytes, whereas when this construct is transfected into ovine preadipocytes and HepG2 cells the construct is inactive and is not inducible by insulin. By contrast, transfection of a construct corresponding to 132 bp of the proximal promoter linked to a luciferase reporter is active and inducible by insulin in all three cell systems. Insulin signalling to the -132 bp construct in differentiated ovine adipocytes involves, in part, an E-box motif at -114. Upstream stimulatory factor (USF)-1 and USF-2, but not sterol regulatory element-binding protein 1 (SREBP-1), are major components of protein complexes that bind this E-box motif. Activation of the 4.3 kb PI construct in differentiated ovine adipocytes is associated with endogenous expression of PI transcripts throughout differentiation; PI transcripts are not detectable by RNase-protection assay in ovine preadipocytes, HepG2 cells or 3T3-F442A adipocytes. These data indicate the presence of repressor motifs in PI that are required to be de-repressed during adipocyte differentiation to allow induction of the promoter by insulin.
Collapse
Affiliation(s)
- M T Travers
- Hannah Research Institute, Hannah Research Park, Ayr KA6 5HL, UK
| | | | | | | | | | | | | |
Collapse
|
15
|
O'Callaghan BL, Koo SH, Wu Y, Freake HC, Towle HC. Glucose regulation of the acetyl-CoA carboxylase promoter PI in rat hepatocytes. J Biol Chem 2001; 276:16033-9. [PMID: 11340083 DOI: 10.1074/jbc.m101557200] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The rat acetyl-CoA carboxylase (ACC) alpha gene is transcribed from two promoters, denoted PI and PII, that direct regulated expression in a tissue-specific manner. Induction of ACC, the rate-controlling enzyme of fatty acid biosynthesis, occurs in the liver in response to feeding of a high carbohydrate, low fat diet, conditions that favor enhanced lipogenesis. This induction is mainly due to increases in PI promoter activity. We have used primary cultured hepatocytes from the rat to investigate glucose regulation of ACC expression. Glucose and insulin synergistically activated expression of ACC mRNAs transcribed from the PI promoter with little or no effect on PII mRNAs. Glucose treatment stimulated PI promoter activity in transfection assays and a glucose-regulated element was identified (-126/-102), homologous to those previously described in other responsive genes, including l-type pyruvate kinase, S(14) and fatty acid synthase. Mutation of this element eliminated the response to glucose. This region of the ACC PI promoter was able to bind a liver nuclear factor designated ChoRF that interacts with other conserved glucose-regulated elements. This ACC PI element is also capable of conferring a strong response to glucose when linked to a heterologous promoter. We conclude that induction of ACC gene expression under lipogenic conditions in hepatocytes is mediated in part by the activation of a glucose-regulated transcription factor, ChoRF, which stimulates transcription from the PI promoter. Similar mechanisms operate on related genes permitting the coordinate induction of the lipogenic pathway.
Collapse
Affiliation(s)
- B L O'Callaghan
- Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | | | | | |
Collapse
|
16
|
Huang C, Freake HC. Thyroid hormone regulates the acetyl-CoA carboxylase PI promoter. Biochem Biophys Res Commun 1998; 249:704-8. [PMID: 9731201 DOI: 10.1006/bbrc.1998.9217] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The acetyl-CoA carboxylase-alpha gene has two promoters, PI and PII. A variety of mRNA products result from this gene, depending on promoter usage and splicing events. We have investigated thyroid hormone regulation of acetyl-CoA carboxylase-alpha gene expression, using the reverse-transcription polymerase chain reaction with PI- or PII-specific primers. RNA was extracted from a range of tissues taken from hypo-, eu-, or hyperthyroid rats. PII-generated products were found in all tissues examined at similar levels and were not affected by thyroid state. Products derived from PI were also widely found but with more variable levels of expression. PI mRNAs were reduced in hypo- and elevated in hyperthyroid livers. In brown adipose tissue, more PI products were found in hypothyroid animals. Thus, thyroid hormone regulates the activity of the acetyl-CoA carboxylase PI promoter to influence fatty acid synthesis in a tissue-specific manner.
Collapse
Affiliation(s)
- C Huang
- Department of Nutritional Sciences, University of Connecticut, Storrs 06269-4017, USA
| | | |
Collapse
|
17
|
Barber MC, Travers MT. Elucidation of a promoter activity that directs the expression of acetyl-CoA carboxylase alpha with an alternative N-terminus in a tissue-restricted fashion. Biochem J 1998; 333 ( Pt 1):17-25. [PMID: 9639557 PMCID: PMC1219550 DOI: 10.1042/bj3330017] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Previous studies in rats and humans have demonstrated that acetyl-CoA carboxylase alpha (ACC-alpha), the principal ACC isoenzyme in lipogenic tissues, is transcribed from two promoters, PI and PII, that operate in a tissue-specific fashion. Each promoter gives rise to ACC-alpha mRNA isoforms that differ in their 5' untranslated regions but essentially encode the same protein product. In the present study we demonstrate that such a pattern of promoter usage is evident in sheep tissues but in addition we have detected the expression of a novel ACC-alpha mRNA isoform that is expressed in a variety of tissues including kidney, lung, liver and mammary gland, where it is markedly induced during lactation. This novel transcript differs from the previously described ACC-alpha mRNA in that exon 5, the primary coding exon in both PI and PII transcripts, is replaced by a 424-nt sequence that seems to represent the 5' terminus of the mRNA. The 424-nt sequence encodes a 17-residue N-terminal region as the N-terminal residue in the deduced sequence is a methionine flanked by several in-frame stop codons. The 5' terminal 424 nt are present as a single exon, which we have termed exon 5A, in the sheep ACC-alpha gene and this is located approx. 15 kb downstream of exon 5 and 5 kb upstream of exon 6. A 1.5 kb HindIII-BglII fragment encompassing the 5' terminus and sequence immediately upstream of exon 5A demonstrates promoter activity when transiently transfected into HepG2 cells and HC11 mouse mammary cells and this is markedly enhanced when insulin is present in the culture medium. Promoter activity is also evident in primary sheep mammary epithelial cells. These results demonstrate the presence of a third promoter, PIII, in the ACC-alpha gene that results in the tissue-restricted expression of an ACC isoenzyme.
Collapse
Affiliation(s)
- M C Barber
- Hannah Research Institute, Ayr KA6 5HL, Scotland, U.K
| | | |
Collapse
|
18
|
Abstract
Long-chain fatty acids are involved in all aspects of cellular structure and function. For controlling amounts of fatty acids, cells are endowed with two acetyl-coenzyme A carboxylase (ACC) systems. ACC-alpha is the rate-limiting enzyme in the biogenesis of long-chain fatty acids, and ACC-beta is believed to control mitochondrial fatty acid oxidation. These two isoforms of ACC control the amount of fatty acids in the cells. Phosphorylation and dephosphorylation of ACC-alpha cause enzyme inactivation and activation, respectively, and serve as the enzyme's short-term regulatory mechanism. Covalently modified enzymes become more sensitive toward cellular metabolites. In addition, many hormones and nutrients affect gene expression. The gene products formed are heterogeneous and tissue specific. The ACC-beta gene is located on human chromosome 12; the cDNA for this gene has just been cloned. The gene for the alpha-isoform is located on human chromosome 17. The catalytic core of the beta-isoform is homologous to that of the alpha-isoform, except for an additional peptide of about 150 amino acids at the N terminus. This extra peptide sequence makes the beta-form about 10,000 daltons larger, and it is thought to be involved in the unique role that has been assigned to this enzyme. The detailed control mechanisms for the beta-isoform are not known.
Collapse
Affiliation(s)
- K H Kim
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907, USA.
| |
Collapse
|