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Gadwal A, Panigrahi P, Khokhar M, Sharma V, Setia P, Vishnoi JR, Elhence P, Purohit P. A critical appraisal of the role of metabolomics in breast cancer research and diagnostics. Clin Chim Acta 2024; 561:119836. [PMID: 38944408 DOI: 10.1016/j.cca.2024.119836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 06/24/2024] [Accepted: 06/24/2024] [Indexed: 07/01/2024]
Abstract
Breast cancer (BC) remains the most prevalent cancer among women worldwide, despite significant advancements in its prevention and treatment. The escalating incidence of BC globally necessitates continued research into novel diagnostic and therapeutic strategies. Metabolomics, a burgeoning field, offers a comprehensive analysis of all metabolites within a cell, tissue, system, or organism, providing crucial insights into the dynamic changes occurring during cancer development and progression. This review focuses on the metabolic alterations associated with BC, highlighting the potential of metabolomics in identifying biomarkers for early detection, diagnosis, treatment and prognosis. Metabolomics studies have revealed distinct metabolic signatures in BC, including alterations in lipid metabolism, amino acid metabolism, and energy metabolism. These metabolic changes not only support the rapid proliferation of cancer cells but also influence the tumour microenvironment and therapeutic response. Furthermore, metabolomics holds great promise in personalized medicine, facilitating the development of tailored treatment strategies based on an individual's metabolic profile. By providing a holistic view of the metabolic changes in BC, metabolomics has the potential to revolutionize our understanding of the disease and improve patient outcomes.
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Affiliation(s)
- Ashita Gadwal
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, 342005, India
| | - Pragyan Panigrahi
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, 342005, India
| | - Manoj Khokhar
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, 342005, India
| | - Vaishali Sharma
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, 342005, India
| | - Puneet Setia
- Department of Forensic Medicine and Toxicology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, 342005, India
| | - Jeewan Ram Vishnoi
- Department of Oncosurgery, All India Institute of Medical Sciences, Jodhpur, Rajasthan, 342005, India
| | - Poonam Elhence
- Department of Pathology, All India Institute of Medical Sciences, Jodhpur Rajasthan, 342005, India
| | - Purvi Purohit
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, 342005, India.
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2
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Ma P, Huang J, Chen B, Huang M, Xiong L, Chen J, Huang S, Liu Y. Lanosterol Synthase Prevents EMT During Lens Epithelial Fibrosis Via Regulating SREBP1. Invest Ophthalmol Vis Sci 2023; 64:12. [PMID: 38079167 PMCID: PMC10715316 DOI: 10.1167/iovs.64.15.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/25/2023] [Indexed: 12/18/2023] Open
Abstract
Purpose Epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) is a predominant pathological process underlying fibrotic cataracts. Here we investigated the role and mechanism of lanosterol synthase (LSS), a key rate-limiting enzyme in sterol biosynthesis, in EMT of LECs. Methods Human lens epithelial explants, primary rabbit LECs, and whole rat lenses were treated with TGFβ2. RNA-sequencing was conducted to explore genetic changes during fibrosis of human lens epithelial explants. Loss- and gain-of-function studies were performed in primary LECs to investigate roles and mechanisms of LSS, lanosterol and sterol regulatory element binding transcription protein 1 (SREBP1) in EMT. Rat lenses were applied to evaluate the potential effect of lanosterol on lens fibrosis. Expression of LSS, SREBP1, EMT-related regulators, and markers were analyzed by Western blot, qRT-PCR, or immunofluorescent staining. Results LSS and steroid biosynthesis were downregulated in TGFβ2-induced lens fibrosis. LSS inhibition directly triggered EMT by inducing Smad2/3 phosphorylation and nucleus translocation, an overexpression of LSS protected LECs from EMT by inhibiting Smad2/3 activation. Moreover, LSS inhibition decreased the expression of SREBP1, which regulated EMT via intervening TGFβ2/Smad2/3 transduction. Furthermore, lanosterol protected LECs from EMT caused by both TGFβ2 treatment and LSS inhibition via suppressing Smad2/3 activation and maintained lens transparency by preventing fibrotic plaques formation. Conclusions We first identified that LSS protected LECs from EMT and played an antifibrotic role to maintain lens transparency. Additionally, lanosterol and sterol biosynthesis regulation might be promising strategies for preventing and treating fibrotic cataracts.
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Affiliation(s)
- Pengjuan Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Jingqi Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Baoxin Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Mi Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Lang Xiong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Jieping Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Shan Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
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3
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Han SI, Nakakuki M, Nakagawa Y, Wang Y, Araki M, Yamamoto Y, Tokiwa H, Takeda H, Mizunoe Y, Motomura K, Ohno H, Kainoh K, Murayama Y, Aita Y, Takeuchi Y, Osaki Y, Miyamoto T, Sekiya M, Matsuzaka T, Yahagi N, Sone H, Daitoku H, Sato R, Kawano H, Shimano H. Rhomboid protease RHBDL4/RHBDD1 cleaves SREBP-1c at endoplasmic reticulum monitoring and regulating fatty acids. PNAS NEXUS 2023; 2:pgad351. [PMID: 37954160 PMCID: PMC10637267 DOI: 10.1093/pnasnexus/pgad351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 10/02/2023] [Indexed: 11/14/2023]
Abstract
The endoplasmic reticulum (ER)-embedded transcription factors, sterol regulatory element-binding proteins (SREBPs), master regulators of lipid biosynthesis, are transported to the Golgi for proteolytic activation to tune cellular cholesterol levels and regulate lipogenesis. However, mechanisms by which the cell responds to the levels of saturated or unsaturated fatty acids remain underexplored. Here, we show that RHBDL4/RHBDD1, a rhomboid family protease, directly cleaves SREBP-1c at the ER. The p97/VCP, AAA-ATPase complex then acts as an auxiliary segregase to extract the remaining ER-embedded fragment of SREBP-1c. Importantly, the enzymatic activity of RHBDL4 is enhanced by saturated fatty acids (SFAs) but inhibited by polyunsaturated fatty acids (PUFAs). Genetic deletion of RHBDL4 in mice fed on a Western diet enriched in SFAs and cholesterol prevented SREBP-1c from inducing genes for lipogenesis, particularly for synthesis and incorporation of PUFAs, and secretion of lipoproteins. The RHBDL4-SREBP-1c pathway reveals a regulatory system for monitoring fatty acid composition and maintaining cellular lipid homeostasis.
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Affiliation(s)
- Song-Iee Han
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Masanori Nakakuki
- Pharmaceutical Research Center, Mochida Pharmaceutical Co., Ltd., Gotemba, Shizuoka 412-8524, Japan
| | - Yoshimi Nakagawa
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- Division of Complex Biosystem Research, Department of Research and Development, Institute of Natural Medicine, University of Toyama, Toyama, Toyama 930-0194, Japan
| | - Yunong Wang
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Masaya Araki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Yuta Yamamoto
- Department of Chemistry, Rikkyo University, Toshima-ku, Tokyo 171-8501, Japan
| | - Hiroaki Tokiwa
- Laboratory of Organic Chemistry, Gifu Pharmaceutical University, Daigaku-Nishi, Gifu 501-1196, Japan
| | - Hiroyuki Takeda
- Division of Proteo Drug Discovery Sciences, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Yuhei Mizunoe
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Kaori Motomura
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Hiroshi Ohno
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Kenta Kainoh
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Yuki Murayama
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Yuichi Aita
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Yoshinori Takeuchi
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Yoshinori Osaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Takafumi Miyamoto
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- Transborder Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Motohiro Sekiya
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Takashi Matsuzaka
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- Transborder Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Naoya Yahagi
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
| | - Hirohito Sone
- Department of Internal Medicine, Faculty of Medicine, Niigata University, Niigata, Niigata 951-8510, Japan
| | - Hiroaki Daitoku
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Ryuichiro Sato
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, Nutri-Life Science Laboratory, The University of Tokyo, Tokyo 113-8657, Japan
| | - Hiroyuki Kawano
- Pharmaceutical Research Center, Mochida Pharmaceutical Co., Ltd., Gotemba, Shizuoka 412-8524, Japan
| | - Hitoshi Shimano
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
- Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Chiyoda-ku, Tokyo 100-0004, Japan
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Ke C, Xiao C, Li J, Wu X, Zhang Y, Chen Y, Sheng S, Fu Z, Wang L, Ni C, Zhao J, Shi Y, Wu Y, Zhong Z, Nan J, Zhu W, Chen J, Wu R, Hu X. FMO2 ameliorates nonalcoholic fatty liver disease by suppressing ER-to-Golgi transport of SREBP1. Hepatology 2023:01515467-990000000-00617. [PMID: 37874228 DOI: 10.1097/hep.0000000000000643] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 09/27/2023] [Indexed: 10/25/2023]
Abstract
BACKGROUND AND AIMS NAFLD comprises a spectrum of liver disorders with the initial abnormal accumulation of lipids in hepatocytes called NAFL, progressing to the more serious NASH in a subset of individuals. Our previous study revealed that global flavin-containing monooxygenase 2 (FMO2) knockout causes higher liver weight in rats. However, the role of FMO2 in NAFLD remains unclear. Herein, we aimed to determine the function and mechanism of FMO2 in liver steatosis and steatohepatitis. APPROACH AND RESULTS The expression of FMO2 was significantly downregulated in patients with NAFL/NASH and mouse models. Both global and hepatocyte-specific knockout of FMO2 resulted in increased lipogenesis and severe hepatic steatosis, inflammation, and fibrosis, whereas FMO2 overexpression in mice improved NAFL/NASH. RNA sequencing showed that hepatic FMO2 deficiency is associated with impaired lipogenesis in response to metabolic challenges. Mechanistically, FMO2 directly interacts with SREBP1 at amino acids 217-296 competitively with SREBP cleavage-activating protein (SCAP) and inhibits SREBP1 translocation from the endoplasmic reticulum (ER) to the Golgi apparatus and its subsequent activation, thus suppressing de novo lipogenesis (DNL) and improving NAFL/NASH. CONCLUSIONS In hepatocytes, FMO2 is a novel molecule that protects against the progression of NAFL/NASH independent of enzyme activity. FMO2 impairs lipogenesis in high-fat diet-induced or choline-deficient, methionine-deficient, amino acid-defined high-fat diet-induced steatosis, inflammation, and fibrosis by directly binding to SREBP1 and preventing its organelle translocation and subsequent activation. FMO2 thus is a promising molecule for targeting the activation of SREBP1 and for the treatment of NAFL/NASH.
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Affiliation(s)
- Changle Ke
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Changchen Xiao
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Jiamin Li
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Xianpeng Wu
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Yu Zhang
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Yongjian Chen
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Shuyuan Sheng
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Zaiyang Fu
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Lingjun Wang
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Cheng Ni
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Jing Zhao
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Yanna Shi
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Yan Wu
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Zhiwei Zhong
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Jinliang Nan
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Wei Zhu
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Jinghai Chen
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
- Institute of Translational Medicine, College of Medicine, Zhejiang University, Hangzhou, P.R.China
| | - Rongrong Wu
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
| | - Xinyang Hu
- Department of Cardiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, P.R.China
- State Key Laboratory of Transvascular Implantation Devices, Hangzhou, P.R.China
- Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, P.R.China
- Research Center for Life Science and Human Health, Binjiang Institute of Zhejiang University, Hangzhou, P.R.China
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Chen M, Lin Y, Dang Y, Xiao Y, Zhang F, Sun G, Jiang X, Zhang L, Du J, Duan S, Zhang X, Qin Z, Yang J, Liu K, Wu B. Reprogramming of rhythmic liver metabolism by intestinal clock. J Hepatol 2023; 79:741-757. [PMID: 37230230 DOI: 10.1016/j.jhep.2023.04.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 04/10/2023] [Accepted: 04/27/2023] [Indexed: 05/27/2023]
Abstract
BACKGROUND & AIMS Temporal oscillations in intestinal nutrient processing and absorption are coordinated by the local clock, which leads to the hypothesis that the intestinal clock has major impacts on shaping peripheral rhythms via diurnal nutritional signals. Here, we investigate the role of the intestinal clock in controlling liver rhythmicity and metabolism. METHODS Transcriptomic analysis, metabolomics, metabolic assays, histology, quantitative (q)PCR, and immunoblotting were performed with Bmal1-intestine-specific knockout (iKO), Rev-erba-iKO, and control mice. RESULTS Bmal1 iKO caused large-scale reprogramming of the rhythmic transcriptome of mouse liver with a limited effect on its clock. In the absence of intestinal Bmal1, the liver clock was resistant to entrainment by inverted feeding and a high-fat diet. Importantly, Bmal1 iKO remodelled diurnal hepatic metabolism by shifting to gluconeogenesis from lipogenesis during the dark phase, leading to elevated glucose production (hyperglycaemia) and insulin insensitivity. Conversely, Rev-erba iKO caused a diversion to lipogenesis from gluconeogenesis during the light phase, resulting in enhanced lipogenesis and an increased susceptibility to alcohol-related liver injury. These temporal diversions were attributed to disruption of hepatic SREBP-1c rhythmicity, which was maintained via gut-derived polyunsaturated fatty acids produced by intestinal FADS1/2 under the control of a local clock. CONCLUSIONS Our findings establish a pivotal role for the intestinal clock in dictating liver rhythmicity and diurnal metabolism, and suggest targeting intestinal rhythms as a new avenue for improving metabolic health. IMPACT AND IMPLICATIONS Our findings establish the centrality of the intestinal clock among peripheral tissue clocks, and associate liver-related pathologies with its malfunction. Clock modifiers in the intestine are shown to modulate liver metabolism with improved metabolic parameters. Such knowledge will help clinicians improve the diagnosis and treatment of metabolic diseases by incorporating intestinal circadian factors.
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Affiliation(s)
- Min Chen
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yanke Lin
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yongkang Dang
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yifei Xiao
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Fugui Zhang
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Guanghui Sun
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xuejun Jiang
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Li Zhang
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jianhao Du
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shuyi Duan
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiaojian Zhang
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Zifei Qin
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| | - Jing Yang
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| | - Kaisheng Liu
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Center for Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, China.
| | - Baojian Wu
- Institute of Molecular Rhythm and Metabolism, Guangzhou University of Chinese Medicine, Guangzhou, China.
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6
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Wang J, Xiang Y, Fan M, Fang S, Hua Q. The Ubiquitin-Proteasome System in Tumor Metabolism. Cancers (Basel) 2023; 15:cancers15082385. [PMID: 37190313 DOI: 10.3390/cancers15082385] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/16/2023] [Accepted: 04/17/2023] [Indexed: 05/17/2023] Open
Abstract
Metabolic reprogramming, which is considered a hallmark of cancer, can maintain the homeostasis of the tumor environment and promote the proliferation, survival, and metastasis of cancer cells. For instance, increased glucose uptake and high glucose consumption, known as the "Warburg effect," play an essential part in tumor metabolic reprogramming. In addition, fatty acids are harnessed to satisfy the increased requirement for the phospholipid components of biological membranes and energy. Moreover, the anabolism/catabolism of amino acids, such as glutamine, cystine, and serine, provides nitrogen donors for biosynthesis processes, development of the tumor inflammatory environment, and signal transduction. The ubiquitin-proteasome system (UPS) has been widely reported to be involved in various cellular biological activities. A potential role of UPS in the metabolic regulation of tumor cells has also been reported, but the specific regulatory mechanism has not been elucidated. Here, we review the role of ubiquitination and deubiquitination modification on major metabolic enzymes and important signaling pathways in tumor metabolism to inspire new strategies for the clinical treatment of cancer.
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Affiliation(s)
- Jie Wang
- Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
| | - Yuandi Xiang
- Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
| | - Mengqi Fan
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Shizhen Fang
- Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
| | - Qingquan Hua
- Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
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7
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Zhao Q, Lin X, Wang G. Targeting SREBP-1-Mediated Lipogenesis as Potential Strategies for Cancer. Front Oncol 2022; 12:952371. [PMID: 35912181 PMCID: PMC9330218 DOI: 10.3389/fonc.2022.952371] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/22/2022] [Indexed: 11/13/2022] Open
Abstract
Sterol regulatory element binding protein-1 (SREBP-1), a transcription factor with a basic helix–loop–helix leucine zipper, has two isoforms, SREBP-1a and SREBP-1c, derived from the same gene for regulating the genes of lipogenesis, including acetyl-CoA carboxylase, fatty acid synthase, and stearoyl-CoA desaturase. Importantly, SREBP-1 participates in metabolic reprogramming of various cancers and has been a biomarker for the prognosis or drug efficacy for the patients with cancer. In this review, we first introduced the structure, activation, and key upstream signaling pathway of SREBP-1. Then, the potential targets and molecular mechanisms of SREBP-1-regulated lipogenesis in various types of cancer, such as colorectal, prostate, breast, and hepatocellular cancer, were summarized. We also discussed potential therapies targeting the SREBP-1-regulated pathway by small molecules, natural products, or the extracts of herbs against tumor progression. This review could provide new insights in understanding advanced findings about SREBP-1-mediated lipogenesis in cancer and its potential as a target for cancer therapeutics.
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Affiliation(s)
- Qiushi Zhao
- National Engineering Laboratory for AIDS Vaccine, Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of Life Sciences, Jilin University, Changchun, China
| | - Xingyu Lin
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, China
- *Correspondence: Xingyu Lin, ; Guan Wang,
| | - Guan Wang
- National Engineering Laboratory for AIDS Vaccine, Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of Life Sciences, Jilin University, Changchun, China
- *Correspondence: Xingyu Lin, ; Guan Wang,
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8
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Zeng H, Qin H, Liao M, Zheng E, Luo X, Xiao A, Li Y, Chen L, Wei L, Zhao L, Ruan XZ, Yang P, Chen Y. CD36 promotes de novo lipogenesis in hepatocytes through INSIG2-dependent SREBP1 processing. Mol Metab 2021; 57:101428. [PMID: 34974159 PMCID: PMC8810570 DOI: 10.1016/j.molmet.2021.101428] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/23/2021] [Accepted: 12/24/2021] [Indexed: 02/08/2023] Open
Abstract
Objective Enhanced de novo lipogenesis (DNL) in hepatocytes is a major contributor to nonalcoholic fatty liver disease (NAFLD). Fatty acid translocase (FAT/CD36) is involved in the pathogenesis of NAFLD through facilitating free fatty acids uptake. Here, we explored the effects of CD36 on DNL and elucidated the underlying mechanisms. Methods We generated hepatocyte-specific CD36 knockout (CD36LKO) mice to study in vivo effects of CD36 on DNL under high-fat diet (HFD). Lipid deposition and DNL were analyzed in primary hepatocytes isolated from CD36LKO mice or HepG2 cells with CD36 overexpression. RNA sequence, co-immunoprecipitation, and proximity ligation assay were carried out to determine its role in regulating DNL. Results Hepatic CD36 expression was upregulated in NAFLD mice and patients, and CD36LKO mice exhibited attenuated HFD-induced hepatic steatosis and insulin resistance. We identified hepatocyte CD36 as a key regulator for DNL in the liver. Sterol regulatory element-binding protein 1 (SREBP1) and its downstream lipogenic enzymes such as FASN, ACCα, and ACLY were significantly downregulated in the liver of HFD-fed CD36LKO mice, whereas overexpression CD36 stimulated insulin-mediated DNL and lipid droplet formation in vitro. Mechanistically, CD36 was activated by insulin and formed a complex with insulin-induced gene-2 (INSIG2) that disrupts the interaction between SREBP cleavage-activating protein (SCAP) and INSIG2, thereby leading to the translocation of SREBP1 from ER to Golgi for processing. Furthermore, treatment with 25-hydroxycholesterol or betulin molecules shown to enhance SCAP–INSIG interaction, reversed the effects of CD36 on SREBP1 cleavage. Conclusions Our findings identify a previously unsuspected role of CD36 in the regulation of hepatic lipogenic program through mediating SREBP1 processing by INSIG2, providing additional evidence for targeting CD36 in NAFLD. CD36 plays a novel role in DNL of hepatocytes beyond its known FFA transport function. CD36 regulates DNL via SREBP1 processing through interaction with INSIG2. Hepatocyte-specific intervention of CD36 is a hopeful therapeutic strategy for NAFLD.
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Affiliation(s)
- Han Zeng
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Hong Qin
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Meng Liao
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Enze Zheng
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Xiaoqing Luo
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Anhua Xiao
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Yiyu Li
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Lin Chen
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Li Wei
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Lei Zhao
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China
| | - Xiong Z Ruan
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China; John Moorhead Research Laboratory, Centre for Nephrology, University College London Medical School, Royal Free Campus, University College London, London NW3 2PF, United Kingdom
| | - Ping Yang
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China.
| | - Yaxi Chen
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, 400016 Chongqing, China.
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9
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SREBP-1c and lipogenesis in the liver: an update1. Biochem J 2021; 478:3723-3739. [PMID: 34673919 DOI: 10.1042/bcj20210071] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/28/2021] [Accepted: 09/30/2021] [Indexed: 12/13/2022]
Abstract
Sterol Regulatory Element Binding Protein-1c is a transcription factor that controls the synthesis of lipids from glucose in the liver, a process which is of utmost importance for the storage of energy. Discovered in the early nineties by B. Spiegelman and by M. Brown and J. Goldstein, it has generated more than 5000 studies in order to elucidate its mechanism of activation and its role in physiology and pathology. Synthetized as a precursor found in the membranes of the endoplasmic reticulum, it has to be exported to the Golgi and cleaved by a mechanism called regulated intramembrane proteolysis. We reviewed in 2002 its main characteristics, its activation process and its role in the regulation of hepatic glycolytic and lipogenic genes. We particularly emphasized that Sterol Regulatory Element Binding Protein-1c is the mediator of insulin effects on these genes. In the present review, we would like to update these informations and focus on the response to insulin and to another actor in Sterol Regulatory Element Binding Protein-1c activation, the endoplasmic reticulum stress.
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10
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Kochan Z, Szupryczynska N, Malgorzewicz S, Karbowska J. Dietary Lipids and Dyslipidemia in Chronic Kidney Disease. Nutrients 2021; 13:3138. [PMID: 34579015 PMCID: PMC8472557 DOI: 10.3390/nu13093138] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/01/2021] [Accepted: 09/07/2021] [Indexed: 12/18/2022] Open
Abstract
The progression of chronic kidney disease (CKD) leads to altered lipid metabolism. CKD patients exhibit high blood triglyceride (TG) levels, reduced concentrations and functionality of high-density lipoproteins (HDL), and elevated levels of atherogenic small, dense, low-density lipoproteins (sdLDL). Disorders of lipid metabolism and other metabolic disturbances place CKD patients at high risk for cardiovascular disease (CVD). Extensive evidence supports the cardioprotective effects of unsaturated fatty acids, including their beneficial effect on serum cholesterol and TG levels. Dietary lipids might therefore be especially important in the nutritional management of CKD. We review current dietary recommendations for fat intake by CKD patients and suggest potential nutritional interventions by emphasizing dietary lipids that might improve the blood lipid profile and reduce cardiovascular risk in CKD.
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Affiliation(s)
- Zdzislaw Kochan
- Laboratory of Nutritional Biochemistry, Department of Clinical Nutrition, Faculty of Health Sciences, Medical University of Gdansk, 80-210 Gdansk, Poland; (Z.K.); (N.S.)
| | - Natalia Szupryczynska
- Laboratory of Nutritional Biochemistry, Department of Clinical Nutrition, Faculty of Health Sciences, Medical University of Gdansk, 80-210 Gdansk, Poland; (Z.K.); (N.S.)
| | - Sylwia Malgorzewicz
- Department of Clinical Nutrition, Division of Clinical Nutrition and Dietetics, Faculty of Health Sciences, Medical University of Gdansk, 80-210 Gdansk, Poland;
- Department of Nephrology, Transplantology and Internal Medicine, Faculty of Medicine, Medical University of Gdansk, 80-210 Gdansk, Poland
| | - Joanna Karbowska
- Department of Biochemistry, Faculty of Medicine, Medical University of Gdansk, 80-210 Gdansk, Poland
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11
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Transcriptomics-Based Phenotypic Screening Supports Drug Discovery in Human Glioblastoma Cells. Cancers (Basel) 2021; 13:cancers13153780. [PMID: 34359681 PMCID: PMC8345128 DOI: 10.3390/cancers13153780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/16/2021] [Accepted: 07/20/2021] [Indexed: 12/11/2022] Open
Abstract
Simple Summary Glioblastoma (GBM) remains a particularly challenging cancer, with an aggressive phenotype and few promising treatment options. Future therapy will rely heavily on diagnosing and targeting aggressive GBM cellular phenotypes, both before and after drug treatment, as part of personalized therapy programs. Here, we use a genome-wide drug-induced gene expression (DIGEX) approach to define the cellular drug response phenotypes associated with two clinical drug candidates, the phosphodiesterase 10A inhibitor Mardepodect and the multi-kinase inhibitor Regorafenib. We identify genes encoding specific drug targets, some of which we validate as effective antiproliferative agents and combination therapies in human GBM cell models, including HMGCoA reductase (HMGCR), salt-inducible kinase 1 (SIK1), bradykinin receptor subtype B2 (BDKRB2), and Janus kinase isoform 2 (JAK2). Individual, personalized treatments will be essential if we are to address and overcome the pharmacological plasticity that GBM exhibits, and DIGEX will play a central role in validating future drugs, diagnostics, and possibly vaccine candidates for this challenging cancer. Abstract We have used three established human glioblastoma (GBM) cell lines—U87MG, A172, and T98G—as cellular systems to examine the plasticity of the drug-induced GBM cell phenotype, focusing on two clinical drugs, the phosphodiesterase PDE10A inhibitor Mardepodect and the multi-kinase inhibitor Regorafenib, using genome-wide drug-induced gene expression (DIGEX) to examine the drug response. Both drugs upregulate genes encoding specific growth factors, transcription factors, cellular signaling molecules, and cell surface proteins, while downregulating a broad range of targetable cell cycle and apoptosis-associated genes. A few upregulated genes encode therapeutic targets already addressed by FDA approved drugs, but the majority encode targets for which there are no approved drugs. Amongst the latter, we identify many novel druggable targets that could qualify for chemistry-led drug discovery campaigns. We also observe several highly upregulated transmembrane proteins suitable for combined drug, immunotherapy, and RNA vaccine approaches. DIGEX is a powerful way of visualizing the complex drug response networks emerging during GBM drug treatment, defining a phenotypic landscape which offers many new diagnostic and therapeutic opportunities. Nevertheless, the extreme heterogeneity we observe within drug-treated cells using this technique suggests that effective pan-GBM drug treatment will remain a significant challenge for many years to come.
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12
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Cancer Metabolism: Phenotype, Signaling and Therapeutic Targets. Cells 2020; 9:cells9102308. [PMID: 33081387 PMCID: PMC7602974 DOI: 10.3390/cells9102308] [Citation(s) in RCA: 214] [Impact Index Per Article: 53.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/10/2020] [Accepted: 10/13/2020] [Indexed: 12/12/2022] Open
Abstract
Aberrant metabolism is a major hallmark of cancer. Abnormal cancer metabolism, such as aerobic glycolysis and increased anabolic pathways, has important roles in tumorigenesis, metastasis, drug resistance, and cancer stem cells. Well-known oncogenic signaling pathways, such as phosphoinositide 3-kinase (PI3K)/AKT, Myc, and Hippo pathway, mediate metabolic gene expression and increase metabolic enzyme activities. Vice versa, deregulated metabolic pathways contribute to defects in cellular signal transduction pathways, which in turn provide energy, building blocks, and redox potentials for unrestrained cancer cell proliferation. Studies and clinical trials are being performed that focus on the inhibition of metabolic enzymes by small molecules or dietary interventions (e.g., fasting, calorie restriction, and intermittent fasting). Similar to genetic heterogeneity, the metabolic phenotypes of cancers are highly heterogeneous. This heterogeneity results from diverse cues in the tumor microenvironment and genetic mutations. Hence, overcoming metabolic plasticity is an important goal of modern cancer therapeutics. This review highlights recent findings on the metabolic phenotypes of cancer and elucidates the interactions between signal transduction pathways and metabolic pathways. We also provide novel rationales for designing the next-generation cancer metabolism drugs.
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13
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Hishikawa D, Yanagida K, Nagata K, Kanatani A, Iizuka Y, Hamano F, Yasuda M, Okamura T, Shindou H, Shimizu T. Hepatic Levels of DHA-Containing Phospholipids Instruct SREBP1-Mediated Synthesis and Systemic Delivery of Polyunsaturated Fatty Acids. iScience 2020; 23:101495. [PMID: 32891885 PMCID: PMC7481256 DOI: 10.1016/j.isci.2020.101495] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/25/2020] [Accepted: 08/19/2020] [Indexed: 12/25/2022] Open
Abstract
Polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA) and arachidonic acid (ARA), play fundamental roles in mammalian physiology. Although PUFA imbalance causes various disorders, mechanisms of the regulation of their systemic levels are poorly understood. Here, we report that hepatic DHA-containing phospholipids (DHA-PLs) determine the systemic levels of PUFAs through the SREBP1-mediated transcriptional program. We demonstrated that liver-specific deletion of Agpat3 leads to a decrease of DHA-PLs and a compensatory increase of ARA-PLs not only in the liver but also in other tissues including the brain. Together with recent findings that plasma lysophosphatidylcholine (lysoPC) is the major source of brain DHA, our results indicate that hepatic AGPAT3 contributes to brain DHA accumulation by supplying DHA-PLs as precursors of DHA-lysoPC. Furthermore, dietary fish oil-mediated suppression of hepatic PUFA biosynthetic program was blunted in liver-specific Agpat3 deletion. Our findings highlight the central role of hepatic DHA-PLs as the molecular rheostat for systemic homeostasis of PUFAs.
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Affiliation(s)
- Daisuke Hishikawa
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan.
| | - Keisuke Yanagida
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Katsuyuki Nagata
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Ayumi Kanatani
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Yoshiko Iizuka
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Fumie Hamano
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan; Life Science Core Faculty, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Megumi Yasuda
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Tadashi Okamura
- Laboratory Animal Medicine, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan; Section of Animal Models, Department of Infectious Diseases, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Hideo Shindou
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan; Department of Lipid Science, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takao Shimizu
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan; Department of Lipidomics, Graduate School of Medicine, the University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
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14
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Butler LM, Perone Y, Dehairs J, Lupien LE, de Laat V, Talebi A, Loda M, Kinlaw WB, Swinnen JV. Lipids and cancer: Emerging roles in pathogenesis, diagnosis and therapeutic intervention. Adv Drug Deliv Rev 2020; 159:245-293. [PMID: 32711004 PMCID: PMC7736102 DOI: 10.1016/j.addr.2020.07.013] [Citation(s) in RCA: 285] [Impact Index Per Article: 71.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/02/2020] [Accepted: 07/16/2020] [Indexed: 02/06/2023]
Abstract
With the advent of effective tools to study lipids, including mass spectrometry-based lipidomics, lipids are emerging as central players in cancer biology. Lipids function as essential building blocks for membranes, serve as fuel to drive energy-demanding processes and play a key role as signaling molecules and as regulators of numerous cellular functions. Not unexpectedly, cancer cells, as well as other cell types in the tumor microenvironment, exploit various ways to acquire lipids and extensively rewire their metabolism as part of a plastic and context-dependent metabolic reprogramming that is driven by both oncogenic and environmental cues. The resulting changes in the fate and composition of lipids help cancer cells to thrive in a changing microenvironment by supporting key oncogenic functions and cancer hallmarks, including cellular energetics, promoting feedforward oncogenic signaling, resisting oxidative and other stresses, regulating intercellular communication and immune responses. Supported by the close connection between altered lipid metabolism and the pathogenic process, specific lipid profiles are emerging as unique disease biomarkers, with diagnostic, prognostic and predictive potential. Multiple preclinical studies illustrate the translational promise of exploiting lipid metabolism in cancer, and critically, have shown context dependent actionable vulnerabilities that can be rationally targeted, particularly in combinatorial approaches. Moreover, lipids themselves can be used as membrane disrupting agents or as key components of nanocarriers of various therapeutics. With a number of preclinical compounds and strategies that are approaching clinical trials, we are at the doorstep of exploiting a hitherto underappreciated hallmark of cancer and promising target in the oncologist's strategy to combat cancer.
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Affiliation(s)
- Lisa M Butler
- Adelaide Medical School and Freemasons Foundation Centre for Men's Health, University of Adelaide, Adelaide, SA 5005, Australia; South Australian Health and Medical Research Institute, Adelaide, SA 5000, Australia
| | - Ylenia Perone
- Department of Surgery and Cancer, Imperial College London, Imperial Centre for Translational and Experimental Medicine, London, UK
| | - Jonas Dehairs
- Laboratory of Lipid Metabolism and Cancer, KU Leuven Cancer Institute, 3000 Leuven, Belgium
| | - Leslie E Lupien
- Program in Experimental and Molecular Medicine, Geisel School of Medicine at Dartmouth, 1 Medical Center Drive, Lebanon, NH 037560, USA
| | - Vincent de Laat
- Laboratory of Lipid Metabolism and Cancer, KU Leuven Cancer Institute, 3000 Leuven, Belgium
| | - Ali Talebi
- Laboratory of Lipid Metabolism and Cancer, KU Leuven Cancer Institute, 3000 Leuven, Belgium
| | - Massimo Loda
- Pathology and Laboratory Medicine, Weill Cornell Medical College, Cornell University, New York, NY 10065, USA
| | - William B Kinlaw
- The Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, 1 Medical Center Drive, Lebanon, NH 03756, USA
| | - Johannes V Swinnen
- Laboratory of Lipid Metabolism and Cancer, KU Leuven Cancer Institute, 3000 Leuven, Belgium.
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15
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Abstract
Cholesterol is an important component of lipids in animal membranes. All living cells can synthesize cholesterol, but the amount of synthesis is not sufficient, and therefore cholesterol synthesized in the liver is delivered to extrahepatic tissues as a form of LDL. The liver is a primary organ to not only synthesize but also catabolize cholesterol into bile acids, which ends up to excrete with the feces. The synthetic and catabolic pathways are precisely regulated under the negative-feedback control system under the transcriptional regulation driven by several transcription factors such as the sterol regulatory element-binding proteins (SREBPs), the liver x receptor, and the farnesoid x receptor. This review summarizes various findings including our recent discoveries in the molecular mechanism of activation of SREBP that is involved in the regulation of hepatic cholesterol biosynthesis, and a novel function of the metabolic end product of cholesterol, bile acids, in skeletal muscles.
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Affiliation(s)
- Ryuichiro Sato
- Department of Applied Biological Chemistry, The University of Tokyo , Tokyo, Japan
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16
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Harayama T, Shimizu T. Roles of polyunsaturated fatty acids, from mediators to membranes. J Lipid Res 2020; 61:1150-1160. [PMID: 32487545 PMCID: PMC7397749 DOI: 10.1194/jlr.r120000800] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/28/2020] [Indexed: 12/20/2022] Open
Abstract
PUFAs, such as AA and DHA, are recognized as important biomolecules, but understanding their precise roles and modes of action remains challenging. PUFAs are precursors for a plethora of signaling lipids, for which knowledge about synthetic pathways and receptors has accumulated. However, due to their extreme diversity and the ambiguity concerning the identity of their cognate receptors, the roles of PUFA-derived signaling lipids require more investigation. In addition, PUFA functions cannot be explained just as lipid mediator precursors because they are also critical for the regulation of membrane biophysical properties. The presence of PUFAs in membrane lipids also affects the functions of transmembrane proteins and peripheral membrane proteins. Although the roles of PUFAs as membrane lipid building blocks were difficult to analyze, the discovery of lysophospholipid acyltransferases (LPLATs), which are critical for their incorporation, advanced our understanding. Recent studies unveiled how LPLATs affect PUFA levels in membrane lipids, and their genetic manipulation became an excellent strategy to study the roles of PUFA-containing lipids. In this review, we will provide an overview of metabolic pathways regulating PUFAs as lipid mediator precursors and membrane components and update recent progress about their functions. Some issues to be solved for future research will also be discussed.
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Affiliation(s)
- Takeshi Harayama
- Department of Biochemistry and National Centre of Competence in Research in Chemical Biology, University of Geneva, CH-1211 Geneva, Switzerland
| | - Takao Shimizu
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan and Department of Lipidomics, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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17
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Dorotea D, Koya D, Ha H. Recent Insights Into SREBP as a Direct Mediator of Kidney Fibrosis via Lipid-Independent Pathways. Front Pharmacol 2020; 11:265. [PMID: 32256356 PMCID: PMC7092724 DOI: 10.3389/fphar.2020.00265] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/24/2020] [Indexed: 12/17/2022] Open
Abstract
Sterol regulatory-element binding proteins (SREBPs) are classical regulators of cellular lipid metabolism in the kidney and other tissues. SREBPs are currently recognized as versatile transcription factors involved in a myriad of cellular processes. Meanwhile, SREBPs have been recognized to mediate lipotoxicity, contributing to the progression of kidney diseases. SREBP1 has been shown to bind to the promoter region of TGFβ, a major pro-fibrotic signaling mechanism in the kidney. Conversely, TGFβ activates SREBP1 transcriptional activity suggesting a positive feedback loop of SREBP1 in TGFβ signaling. Public ChIP-seq data revealed numerous non-lipid transcriptional targets of SREBPs that plausibly play roles in progressive kidney disease and fibrosis. This review provides new insights into SREBP as a mediator of kidney fibrosis via lipid-independent pathways.
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Affiliation(s)
- Debra Dorotea
- Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans University, Seoul, South Korea
| | - Daisuke Koya
- Department of Internal Medicine, Kanazawa Medical University, Ishikawa, Japan
| | - Hunjoo Ha
- Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans University, Seoul, South Korea
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18
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Xu H, Luo J, Tian H, Li J, Zhang X, Chen Z, Li M, Loor JJ. Rapid communication: lipid metabolic gene expression and triacylglycerol accumulation in goat mammary epithelial cells are decreased by inhibition of SREBP-1. J Anim Sci 2018; 96:2399-2407. [PMID: 29846631 DOI: 10.1093/jas/sky069] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 05/23/2018] [Indexed: 12/21/2022] Open
Abstract
In mammals, sterol regulatory element binding protein-1 (SREBP-1) is the master regulator of fatty acid and triacylglycerol synthesis. Recent gene silencing studies in mammary cells indicate that SREBP-1 has a central role in milk fat synthesis. However, SREBP-1 knockdown studies in goat mammary cells have not been performed; hence, its direct role in controlling mRNA expression of lipid metabolism genes and triacylglycerol synthesis remains unknown. Inhibition of SREBP-1 in goat mammary epithelial cells (GMEC) by small interference RNA (siRNA) markedly reduced the content of cellular triacylglycerol (~50% decrease, P < 0.05) and was partly related to downregulation of AGPAT6, LPIN1, and DGAT2 (-23%, -28% and -19%, respectively. P < 0.05), which are key enzymes involved in triacylglycerol synthesis, cellular triacylglycerol content and lipid droplet accumulation all decreased by SREBP-1 inhibition. The expression of lipid droplet formation and secretion genes was not altered in response to treatment. Although the lack of effect on expression of ACACA and FASN (rate-limiting enzymes for de novo fatty acid synthesis) with SREBP-1 knockdown was unexpected (P > 0.05), the downregulation of genes related to synthesis of acetyl-CoA and acetate activation (ACLY, ACSS2, and IDH1, P < 0.05) suggests that lipogenesis was inhibited. SREBP-1 knockdown also resulted in decreased expression of genes associated with fatty acid desaturation and elongation (SCD1 and ELOVL6, P < 0.05), long-chain fatty acid (LCFA) activation and transport (ACSL1, FABP3, and SLC27A6, P < 0.05). The results underscored the essential role of SREBP-1 not only in fatty acid synthesis but also in desaturation, elongation, and esterification in GMEC. Clearly, the lack of effect on ACACA and FASN, both of which are considered the key lipogenic enzymes, implies that there may be different regulatory mechanisms in goat compared with bovine mammary cells.
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Affiliation(s)
- Huifen Xu
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, P. R. China.,College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, P.R. China
| | - Jun Luo
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, P. R. China
| | - Huibin Tian
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, P. R. China
| | - Jun Li
- College of Animal Science and Technology, Henan University of Animal Husbandry and Economy, Zhengzhou, Henan, P.R. China
| | - Xueying Zhang
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, P. R. China
| | - Zhi Chen
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, P. R. China
| | - Ming Li
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, P.R. China
| | - Juan J Loor
- Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana, IL
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19
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Cheng X, Li J, Guo D. SCAP/SREBPs are Central Players in Lipid Metabolism and Novel Metabolic Targets in Cancer Therapy. Curr Top Med Chem 2018; 18:484-493. [PMID: 29788888 DOI: 10.2174/1568026618666180523104541] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/02/2017] [Accepted: 01/03/2018] [Indexed: 01/09/2023]
Abstract
Lipid metabolism reprogramming emerges as a new hallmark of malignancies. Sterol regulatory element-binding proteins (SREBPs), which are central players in lipid metabolism, are endoplasmic reticulum (ER)-bound transcription factors that control the expression of genes important for lipid synthesis and uptake. Their transcriptional activation requires binding to SREBP cleavageactivating protein (SCAP) to translocate their inactive precursors from the ER to the Golgi to undergo cleavage and subsequent nucleus translocation of their NH2-terminal forms. Recent studies have revealed that SREBPs are markedly upregulated in human cancers, providing the mechanistic link between lipid metabolism alterations and malignancies. Pharmacological or genetic inhibition of SCAP or SREBPs significantly suppresses tumor growth in various cancer models, demonstrating that SCAP/SREBPs could serve as promising metabolic targets for cancer therapy. In this review, we will summarize recent progress in our understanding of the underlying molecular mechanisms regulating SCAP/SREBPs and lipid metabolism in malignancies, discuss new findings about SREBP trafficking, which requires SCAP N-glycosylation, and introduce a newly identified microRNA-29-mediated negative feedback regulation of the SCAP/SREBP pathway. Moreover, we will review recently developed inhibitors targeting the SCAP/SREBP pathway for cancer treatment.
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Affiliation(s)
- Xiang Cheng
- Department of Radiation Oncology, The Ohio State University James Comprehensive Cancer Center and College of Medicine, Columbus, OH 43210, United States
| | - Jianying Li
- Department of Radiation Oncology, The Ohio State University James Comprehensive Cancer Center and College of Medicine, Columbus, OH 43210, United States
| | - Deliang Guo
- Department of Radiation Oncology, The Ohio State University James Comprehensive Cancer Center and College of Medicine, Columbus, OH 43210, United States
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20
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Albracht-Schulte K, Kalupahana NS, Ramalingam L, Wang S, Rahman SM, Robert-McComb J, Moustaid-Moussa N. Omega-3 fatty acids in obesity and metabolic syndrome: a mechanistic update. J Nutr Biochem 2018; 58:1-16. [PMID: 29621669 DOI: 10.1016/j.jnutbio.2018.02.012] [Citation(s) in RCA: 166] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/24/2018] [Accepted: 02/22/2018] [Indexed: 02/06/2023]
Abstract
Strategies to reduce obesity have become public health priorities as the prevalence of obesity has risen in the United States and around the world. While the anti-inflammatory and hypotriglyceridemic properties of long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) are well known, their antiobesity effects and efficacy against metabolic syndrome, especially in humans, are still under debate. In animal models, evidence consistently suggests a role for n-3 PUFAs in reducing fat mass, particularly in the retroperitoneal and epididymal regions. In humans, however, published research suggests that though n-3 PUFAs may not aid weight loss, they may attenuate further weight gain and could be useful in the diet or as a supplement to help maintain weight loss. Proposed mechanisms by which n-3 PUFAs may work to improve body composition and counteract obesity-related metabolic changes include modulating lipid metabolism; regulating adipokines, such as adiponectin and leptin; alleviating adipose tissue inflammation; promoting adipogenesis and altering epigenetic mechanisms.
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Affiliation(s)
- Kembra Albracht-Schulte
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA; Obesity Research Cluster, Texas Tech University, Lubbock, TX, USA
| | - Nishan Sudheera Kalupahana
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA; Obesity Research Cluster, Texas Tech University, Lubbock, TX, USA; Department of Physiology, Faculty of Medicine, University of Peradeniya, Peradeniya, Sri Lanka.
| | - Latha Ramalingam
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA; Obesity Research Cluster, Texas Tech University, Lubbock, TX, USA
| | - Shu Wang
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA; Obesity Research Cluster, Texas Tech University, Lubbock, TX, USA
| | - Shaikh Mizanoor Rahman
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA; Obesity Research Cluster, Texas Tech University, Lubbock, TX, USA
| | - Jacalyn Robert-McComb
- Obesity Research Cluster, Texas Tech University, Lubbock, TX, USA; Department of Kinesiology, Texas Tech University, Lubbock, TX, USA
| | - Naima Moustaid-Moussa
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX, USA; Obesity Research Cluster, Texas Tech University, Lubbock, TX, USA.
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21
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Abstract
Cellular lipid metabolism and homeostasis are controlled by sterol regulatory-element binding proteins (SREBPs). In addition to performing canonical functions in the transcriptional regulation of genes involved in the biosynthesis and uptake of lipids, genome-wide system analyses have revealed that these versatile transcription factors act as important nodes of convergence and divergence within biological signalling networks. Thus, they are involved in myriad physiological and pathophysiological processes, highlighting the importance of lipid metabolism in biology. Changes in cell metabolism and growth are reciprocally linked through SREBPs. Anabolic and growth signalling pathways branch off and connect to multiple steps of SREBP activation and form complex regulatory networks. In addition, SREBPs are implicated in numerous pathogenic processes such as endoplasmic reticulum stress, inflammation, autophagy and apoptosis, and in this way, they contribute to obesity, dyslipidaemia, diabetes mellitus, nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, chronic kidney disease, neurodegenerative diseases and cancers. This Review aims to provide a comprehensive understanding of the role of SREBPs in physiology and pathophysiology at the cell, organ and organism levels.
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Affiliation(s)
- Hitoshi Shimano
- Department of Internal Medicine (Endocrinology and Metabolism), Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- Life Science Center, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba 305-8577, Japan
- AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Ryuichiro Sato
- AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo 100-0004, Japan
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
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22
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Shimano H. [SREBP-1c and Elovl6 as Targets for Obesity-related Disorders]. YAKUGAKU ZASSHI 2016; 135:1003-9. [PMID: 26329544 DOI: 10.1248/yakushi.15-00175-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent studies suggest that chronic local inflammation and cellular stresses are the key steps in organ defects in obesity-related diseases such as atherosclerosis, diabetes, and fatty liver. We have shown that an excess energy state activates sterol regulatory element-binding protein (SREBP)-1c, a master transcription factor for fatty acid synthesis causing the accumulation of lipids leading to fatty liver, insulin resistance, insulin secretion defects, and dyslipidemia and we clarified their molecular mechanisms. Recently, we shifted focus to the quality aspect of accumulated lipids. It has long been known that saturated and poly-unsaturated fatty acids are atherogenic and anti-atherogenic, respectively. Besides desaturation, we found that the chain-length of fatty acids is another important factor. Elovl6 that we have cloned as an SREBP-1 target is a fatty acid elongase that catalises the last step of fatty acid synthesis. Elovl6 KO mice exhibit obesity and fatty liver on a high energy diet, but unexpectedly were immune to insulin resistance (Nat. Med., 13, 2007, Matsuzaka et al.), atherosclerosis (Arterioscler. Thromb. Vasc. Biol., 31, 2011, Saito et al.) and non-alcoholic steatohepatitis (NASH) pathology including liver damage, ROS, and fibrosis (Hepatology, 56, 2012, Matsuzaka et al.). Elovl6 is crucial for protection against lung fibrosis (Nat. Commun., 4, 2013, Sunaga et al.). These data implicate that fatty acid composition is a new therapeutic target for a variety of chronic metabolic diseases. In this symposium review, a novel strategy for the prevention of life-related diseases will be discussed in the standpoint of application of wet-dry fusion strategies for theoretical and medicinal chemistry.
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Affiliation(s)
- Hitoshi Shimano
- Department of Internal Medicine (Endocrinology and Metabolism), Faculty of Medicine, University of Tsukuba
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23
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Gao LL, Li M, Wang Q, Liu SA, Zhang JQ, Cheng J. HCBP6 Modulates Triglyceride Homeostasis in Hepatocytes Via the SREBP1c/FASN Pathway. J Cell Biochem 2016; 116:2375-84. [PMID: 25855506 DOI: 10.1002/jcb.25188] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 04/03/2015] [Indexed: 02/06/2023]
Abstract
Hypertriglyceridemia leads to liver steatosis, cardiovascular disease, and type 2 diabetes. Although HCBP6 (hepatitis C virus core-binding protein 6) was previously shown to be an HCV (hepatitis C virus) core-binding protein, its biological function remains unclear. Here, we demonstrate that HCBP6 negatively regulates intracellular triglyceride (TG) levels in hepatocytes. We found that bidirectional manipulation of hepatocyte HCBP6 expression by knockdown or overexpression results in increased or decreased TG accumulation, respectively. In addition, HCBP6 mRNA and protein levels exhibited significant time- and dose-dependent increases in a cellular model of lipid-overload hepatic steatosis. Furthermore, TG levels are regulated by HCBP6-sterol regulatory element binding protein 1c (SREBP1c)-mediated fatty acid synthase (FASN) expression. We also demonstrate that HCBP6 mRNA and protein expression is inhibited by microRNA-122 (miR-122), and miR-122 overexpression elicited more robust translational repression of luciferase activity driven by the full 3'-UTR of HCBP6. Taken together, our results provide new evidence that miR-122-regulated HCBP6 functions as a sensor protein to maintain intrahepatocyte TG levels.
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Affiliation(s)
- Li-Li Gao
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, 100015, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, 100015, China
| | - Min Li
- The First Hospital of Lanzhou University, Gansu Province, Gansu, 730000, China
| | - Qi Wang
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, 100015, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, 100015, China
| | - Shun-Ai Liu
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, 100015, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, 100015, China
| | - Jin-Qian Zhang
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, 100015, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, 100015, China
| | - Jun Cheng
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, 100015, China.,Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, 100015, China
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24
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Abstract
The endoplasmic reticulum is the port of entry for proteins into the secretory pathway and the site of synthesis for several important lipids, including cholesterol, triacylglycerol, and phospholipids. Protein production within the endoplasmic reticulum is tightly regulated by a cohort of resident machinery that coordinates the folding, modification, and deployment of secreted and integral membrane proteins. Proteins failing to attain their native conformation are degraded through the endoplasmic reticulum-associated degradation (ERAD) pathway via a series of tightly coupled steps: substrate recognition, dislocation, and ubiquitin-dependent proteasomal destruction. The same ERAD machinery also controls the flux through various metabolic pathways by coupling the turnover of metabolic enzymes to the levels of key metabolites. We review the current understanding and biological significance of ERAD-mediated regulation of lipid metabolism in mammalian cells.
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Affiliation(s)
- Julian Stevenson
- Program in Metabolic Biology, Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720;
| | - Edmond Y Huang
- Program in Metabolic Biology, Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720;
| | - James A Olzmann
- Program in Metabolic Biology, Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720;
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25
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Wang B, Fu J, Li L, Gong D, Wen X, Yu P, Zeng Z. Medium-chain fatty acid reduces lipid accumulation by regulating expression of lipid-sensing genes in human liver cells with steatosis. Int J Food Sci Nutr 2016; 67:288-97. [PMID: 26932533 DOI: 10.3109/09637486.2016.1153611] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Accumulation of lipids in the liver can lead to cell dysfunction and steatosis, an important factor in pathogenesis causing non-alcoholic fatty liver disease. The mechanisms related to lipid deposition in the liver, however, remain poorly understood. This study was aimed to investigate the effects of medium-chain fatty acid (MCFA) on the lipolysis and expression of lipid-sensing genes in human liver cells with steatosis. A cellular steatosis model, which is suitable to experimentally investigate the impact of fat accumulation in the liver, was established in human normal liver cells (LO2 cells) with a mixture of free fatty acids (oleate/palmitate, 2:1) at 200 μm for 24 h incubation. MCFA was found to down-regulate expression of liver X receptor-α, sterol regulatory element binding protein-1, acetyl-CoA carboxylase, fatty acid synthase, CD 36 and lipoprotein lipase in this cellular model, and have positive effects on adipose triglyceride lipase and hormone-sensitive lipase. These results suggest that MCFA may reduce lipid accumulation by regulating key lipid-sensing genes in human liver cells with steatosis.
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Affiliation(s)
- Baogui Wang
- a State Key Laboratory of Food Science and Technology , Nanchang University , Nanchang , China
| | - Jing Fu
- a State Key Laboratory of Food Science and Technology , Nanchang University , Nanchang , China
| | - Lumin Li
- a State Key Laboratory of Food Science and Technology , Nanchang University , Nanchang , China
| | - Deming Gong
- b School of Biological Sciences , The University of Auckland , Auckland , New Zealand
| | - Xuefang Wen
- c School of Resource and Environmental and Chemical Engineering , Nanchang University , Nanchang , China
| | - Ping Yu
- c School of Resource and Environmental and Chemical Engineering , Nanchang University , Nanchang , China
| | - Zheling Zeng
- a State Key Laboratory of Food Science and Technology , Nanchang University , Nanchang , China ;,c School of Resource and Environmental and Chemical Engineering , Nanchang University , Nanchang , China
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26
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Deng X, Dong Q, Bridges D, Raghow R, Park EA, Elam MB. Docosahexaenoic acid inhibits proteolytic processing of sterol regulatory element-binding protein-1c (SREBP-1c) via activation of AMP-activated kinase. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:1521-9. [PMID: 26327595 DOI: 10.1016/j.bbalip.2015.08.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 08/06/2015] [Accepted: 08/24/2015] [Indexed: 11/27/2022]
Abstract
In hyperinsulinemic states including obesity and T2DM, overproduction of fatty acid and triglyceride contributes to steatosis of the liver, hyperlipidemia and hepatic insulin resistance. This effect is mediated in part by the transcriptional regulator sterol responsive element binding protein-1c (SREBP-1c), which stimulates the expression of genes involved in hepatic fatty acid and triglyceride synthesis. SREBP-1c is up regulated by insulin both via increased transcription of nascent full-length SREBP-1c and by enhanced proteolytic processing of the endoplasmic reticulum (ER)-bound precursor to yield the transcriptionally active n-terminal form, nSREBP-1c. Polyunsaturated fatty acids of marine origin (n-3 PUFA) prevent induction of SREBP-1c by insulin thereby reducing plasma and hepatic triglycerides. Despite widespread use of n-3 PUFA supplements to reduce triglycerides in clinical practice, the exact mechanisms underlying their hypotriglyceridemic effect remain elusive. Here we demonstrate that the n-3 PUFA docosahexaenoic acid (DHA; 22:5 n-3) reduces nSREBP-1c by inhibiting regulated intramembrane proteolysis (RIP) of the nascent SREBP-1c. We further show that this effect of DHA is mediated both via activation of AMP-activated protein kinase (AMPK) and by inhibition of mechanistic target of rapamycin complex 1 (mTORC1). The inhibitory effect of AMPK on SREBP-1c processing is linked to phosphorylation of serine 365 of SREBP-1c in the rat. We have defined a novel regulatory mechanism by which n-3 PUFA inhibit induction of SREBP-1c by insulin. These findings identify AMPK as an important negative regulator of hepatic lipid synthesis and as a potential therapeutic target for hyperlipidemia in obesity and T2DM.
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Affiliation(s)
- Xiong Deng
- Department of Veterans Affairs Medical Center, 1030 Jefferson Avenue, Memphis TN 38104, United States; Department of Pharmacology, 874 Union Avenue, Memphis, TN 38163, United States.
| | - Qingming Dong
- Department of Pharmacology, 874 Union Avenue, Memphis, TN 38163, United States
| | - Dave Bridges
- Department of Physiology, 894 Union Avenue, Memphis TN 38163, United States; Children's Foundation Research Institute, Le Bonheur Children's Hospital, Department of Pediatrics, University of Tennessee Health Science Center, 50 North Dunlap, Memphis TN 38103, United States
| | - Rajendra Raghow
- Department of Veterans Affairs Medical Center, 1030 Jefferson Avenue, Memphis TN 38104, United States; Department of Pharmacology, 874 Union Avenue, Memphis, TN 38163, United States
| | - Edwards A Park
- Department of Veterans Affairs Medical Center, 1030 Jefferson Avenue, Memphis TN 38104, United States; Department of Pharmacology, 874 Union Avenue, Memphis, TN 38163, United States
| | - Marshall B Elam
- Department of Veterans Affairs Medical Center, 1030 Jefferson Avenue, Memphis TN 38104, United States; Department of Pharmacology, 874 Union Avenue, Memphis, TN 38163, United States
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27
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Rousseaux J, Duhamel A, Dumont J, Dallongeville J, Molnar D, Widhalm K, Manios Y, Sjöström M, Kafatos A, Breidenassel C, Gonzales-Gross M, Cuenca-Garcia M, Censi L, Ascensión M, De Henauw S, Moreno LA, Meirhaeghe A, Gottrand F. The n-3 long-chain PUFAs modulate the impact of the GCKR Pro446Leu polymorphism on triglycerides in adolescents. J Lipid Res 2015; 56:1774-80. [PMID: 26136510 DOI: 10.1194/jlr.m057570] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Indexed: 01/19/2023] Open
Abstract
Dietary n-3 long-chain PUFAs (LC-PUFAs) are associated with improvement in the parameters of the metabolic syndrome (MetS). Glucokinase regulatory protein (GCKR) is a key protein regulating intracellular glucose disposal. Our aim was to investigate: i) the relationship between the GCKR rs1260326 (Pro446Leu) polymorphism and parameters of the MetS; and ii) a potential influence of n-3 and n-6 LC-PUFA levels on this relationship in the HELENA study (1,155 European adolescents). Linear regression analyses were performed to study the association between rs1260326 and the outcomes of interest. Interactions between rs1260326 and LC-PUFA levels on outcomes were explored. The T allele of rs1260326 was associated with higher serum TG concentrations compared with the C allele. In contrast to n-6 LC-PUFA levels, a significant interaction (P = 0.01) between rs1260326 and total n-3 LC-PUFA levels on serum TG concentrations was observed. After stratification on the n-3 LC-PUFA median values, the association between rs1260326 and TG concentration was significant only in the group with high n-3 LC-PUFA levels. In conclusion, this is the first evidence that n-3 LC-PUFAs may modulate the impact of the GCKR rs1260326 polymorphism on TG concentrations in adolescents. Several molecular mechanisms, in link with glucose uptake, could explain these findings.
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Affiliation(s)
- Julien Rousseaux
- Inserm U995, LIRIC, CHU Lille, University Lille, Lille, France Unité de Biostatistiques, CERIM, EA2694, CHU Lille, University Lille, Lille, France
| | - Alain Duhamel
- Unité de Biostatistiques, CERIM, EA2694, CHU Lille, University Lille, Lille, France
| | - Julie Dumont
- Inserm UMR1167, Institut Pasteur de Lille, University Lille, Lille, France
| | - Jean Dallongeville
- Inserm UMR1167, Institut Pasteur de Lille, University Lille, Lille, France
| | - Denes Molnar
- Department of Pediatrics, University of Pécs, Pécs, Hungary
| | - Kurt Widhalm
- Academic Institute for Clinical Nutrition, Vienna, Austria and Private Medical University Salzburg, Salzburg, Austria
| | - Yannis Manios
- Department of Nutrition and Dietetics, Harokopio University, Athens, Greece
| | - Michael Sjöström
- Unit for Preventive Nutrition, Department of Biosciences and Nutrition, Karolinska Institute, Huddinge, Sweden
| | - Anthony Kafatos
- Preventive Medicine and Nutrition Unit, School of Medicine, University of Crete, Heraklion, Greece
| | - Christina Breidenassel
- Institut für Ernährungs-und Lebensmittelwissenschaften, Humanernährung, Rheinische Friedrich-Wilhelms, Universität Bonn, Bonn, Germany
| | - Marcela Gonzales-Gross
- Facultad de la Actividad Física y del Deporte-INEF, Universidad Politécnica de Madrid, Madrid, Spain
| | | | - Laura Censi
- National Research Institute on Food and Nutrition, Rome, Italy
| | - Marcos Ascensión
- Immunonutrition Research Group, Department of Metabolism and Nutrition, Institute of Food Science and Technology and Nutrition (ICTAN-CSIC), Madrid, Spain
| | - Stefaan De Henauw
- Department of Public Health, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Luis A Moreno
- GENUD (Growth, Exercise, Nutrition and Development) Research Group, Escuela Universitaria de Ciencias de la Salud, Universidad de Zaragoza, Zaragoza, Spain
| | - Aline Meirhaeghe
- Inserm UMR1167, Institut Pasteur de Lille, University Lille, Lille, France
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28
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Wang XC, Zhan XR, Li XY, Yu JJ, Liu XM. MicroRNA-185 regulates expression of lipid metabolism genes and improves insulin sensitivity in mice with non-alcoholic fatty liver disease. World J Gastroenterol 2014; 20:17914-17923. [PMID: 25548489 PMCID: PMC4273141 DOI: 10.3748/wjg.v20.i47.17914] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 08/16/2014] [Accepted: 09/19/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To assess the regulatory effect of microRNA-185 (miR-185) on lipid metabolism and the insulin signalling pathway in human HepG2 hepatocytes and a high-fat diet mouse model.
METHODS: Quantitative reverse transcription-polymerase chain reaction was used to assess the mRNA levels of lipogenic genes after loss or gain of miR-185. In addition, the amounts of insulin signalling intermediates were determined after transfection of HepG2 cells with pre-miR-185.
RESULTS: MiR-185 levels decreased in a time- and dose-dependent manner in response to palmitic acid in human HepG2 hepatocytes. Transfection of HepG2 cells with miR-185 significantly decreased the mRNA levels of fatty acid synthase, 3-hydroxy-3-methylglutaryl-CoA reductase, sterol-regulatory element binding protein-2, and sterol-regulatory element binding protein-1c, whereas inhibition of miR-185 using an anti-miR-185 oligonucleotide produced the opposite effect in HepG2 cells. In a high-fat diet mouse model, the accumulation of lipids was significantly improved after treatment with miR-185, compared with control animals. Induction of miR-185 enhanced the insulin signalling pathway by up-regulating the insulin-receptor substrate-2.
CONCLUSION: These findings suggest that miR-185 plays an important role in regulating fatty-acid metabolism and cholesterol homeostasis in hepatocytes, as well as in improving insulin sensitivity, both in vitro and in vivo.
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