1
|
Guimarães LC, Fidale TM, Pereira TCR, Lopes PR, Ferreira-Junior MD, Deconte SR, Ferreira-Neto ML, Brito WS, Gomes RM, de Souza FR, Cavalcante KVN, Herrera GC, de Moura FBR, Resende ES. Cardioprotective Effects of Leucine Supplementation against Doxorubicin-Induced Cardiotoxicit. Cardiovasc Toxicol 2024; 24:122-132. [PMID: 38165500 DOI: 10.1007/s12012-023-09817-2] [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: 08/08/2023] [Accepted: 11/18/2023] [Indexed: 01/03/2024]
Abstract
Doxorubicin is one of the most important antitumor drugs used in oncology; however, its cardiotoxic effect limits the therapeutic use and raises concerns regarding patient prognosis. Leucine is a branched-chain amino acid used in dietary supplementation and has been studied to attenuate the toxic effects of doxorubicin in animals, which increases oxidative stress. Oxidative stress in different organs can be estimated using several methods, including catalase expression analysis. This study aimed to analyze the effect of leucine on catalase levels in rat hearts after doxorubicin administration. Adult male Wistar rats were separated into two groups: Standard diet (SD) and 5% Leucine-Enriched Diet (LED). The animals had free access to diet from D0 to D28. At D14, the groups were subdivided in animals injected with Doxorubicin and animals injected with vehicle, until D28, and the groups were SD, SD + Dox, LED and LED + Dox. At D28, the animals were submitted do Transthoracic Echocardiography and euthanized. Despite Dox groups had impaired body weight gain, raw heart weight was not different between the groups. No substantial alterations were observed in macroscopic evaluation of the heart. Although, Doxorubicin treatment increased total interstitial collagen in the heart, which in addition to Type I collagen, is lower in LED groups. Western blot analysis showed that catalase expression in the heart of LED groups was lower than that in SD groups. In conclusion, leucine supplementation reduced both the precocious Dox-induced cardiac remodeling and catalase levels in the heart.
Collapse
Affiliation(s)
- Lucas C Guimarães
- Laboratory of Experimental Medicine, Department of Health Sciences - PGCS, Faculty of Medicine, Federal University of Uberlândia, Uberlândia, Brazil.
| | - Thiago M Fidale
- Biotechnology Institute. Department of Medicine, Federal University of Catalão, Catalão, Goiás, Brazil
| | - Talita C R Pereira
- Institute of Biomedical Sciences, Department of Physiology, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - Paulo R Lopes
- School of Dentistry-FOAr, Department of Physiology and Pathology, Universidade Estadual Paulista "Júlio de Mesquita Filho"-UNESP, Araraquara, SP, Brazil
| | - Marcos D Ferreira-Junior
- Laboratory of Endocrine Physiology and Metabolism, ICB, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Simone R Deconte
- UFU-ICBIM. Department of Physiology and Biophysics, Federal University of Uberlândia, Uberlândia, Brazil
| | - Marcos L Ferreira-Neto
- UFU-ICBIM. Department of Physiology and Biophysics, Federal University of Uberlândia, Uberlândia, Brazil
| | | | - Rodrigo M Gomes
- Laboratory of Endocrine Physiology and Metabolism, ICB, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Fernanda R de Souza
- Laboratory of Experimental Medicine, Department of Medicine, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - Keilah V N Cavalcante
- Laboratory of Endocrine Physiology and Metabolism, ICB, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Gustavo C Herrera
- The Veterinary Hospital, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | | | - Elmiro S Resende
- Laboratory of Experimental Medicine, Department of Health Sciences - PGCS, Faculty of Medicine, Federal University of Uberlândia, Uberlândia, Brazil
- Postgraduate Program in Health Sciences-PGCS, Faculty of Medicine, Federal University of Uberlândia, Uberlândia, MG, Brazil
| |
Collapse
|
2
|
From the Bench to the Bedside: Branched Amino Acid and Micronutrient Strategies to Improve Mitochondrial Dysfunction Leading to Sarcopenia. Nutrients 2022; 14:nu14030483. [PMID: 35276842 PMCID: PMC8838610 DOI: 10.3390/nu14030483] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/17/2022] [Accepted: 01/19/2022] [Indexed: 02/01/2023] Open
Abstract
With extended life expectancy, the older population is constantly increasing, and consequently, so too is the prevalence of age-related disorders. Sarcopenia, the pathological age-related loss of muscle mass and function; and malnutrition, the imbalance in nutrient intake and resultant energy production, are both commonly occurring conditions in old adults. Altered nutrition plays a crucial role in the onset of sarcopenia, and both these disorders are associated with detrimental consequences for patients (e.g., frailty, morbidity, and mortality) and society (e.g., healthcare costs). Importantly, sarcopenia and malnutrition also share critical molecular alterations, such as mitochondrial dysfunction, increased oxidative stress, and a chronic state of low grade and sterile inflammation, defined as inflammageing. Given the connection between malnutrition and sarcopenia, nutritional interventions capable of affecting mitochondrial health and correcting inflammageing are emerging as possible strategies to target sarcopenia. Here, we discuss mitochondrial dysfunction, oxidative stress, and inflammageing as key features leading to sarcopenia. Moreover, we examine the effects of some branched amino acids, omega-3 PUFA, and selected micronutrients on these pathways, and their potential role in modulating sarcopenia, warranting further clinical investigation.
Collapse
|
3
|
Zhang T, Wang Y, Yu H, Zhang T, Guo L, Xu J, Wei X, Wang N, Wu Y, Wang X, Huang L. PGK1 represses autophagy-mediated cell death to promote the proliferation of liver cancer cells by phosphorylating PRAS40. Cell Death Dis 2022; 13:68. [PMID: 35058442 PMCID: PMC8776853 DOI: 10.1038/s41419-022-04499-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 12/07/2021] [Accepted: 12/30/2021] [Indexed: 01/18/2023]
Abstract
Autophagy predominantly promotes cell survival by recycling cell components, while it kills cells in specific contexts. Cell death related to autophagy plays important roles in multiple physiological and pathological situations including tumorigenesis, and the mechanism needs to be defined further. PRAS40 was found to be crucial in various cancers, and phosphorylation was reported to be involved in autophagy inhibition in monocytes. However, the detailed role of PRAS40 in autophagy and the relationship to tumorigenesis remain largely unknown. Herein we screened the binding partners of PRAS40, and found that PRAS40 interacted with Phosphoglycerate kinase 1 (PGK1). PGK1 phosphorylated PRAS40 at Threonine 246, which could be inhibited by blocking the interaction. Both in vitro and in vivo results revealed that PRAS40 mediated PGK1-induced cell growth. By tracing the mechanism, we found that PGK1 suppressed autophagy-mediated cell death, in which PRAS40 was crucial. Thus PGK1 phosphorylates PRAS40 to repress autophagy-mediated cell death under normoxia, promoting cellular proliferation. The binding of PGK1 to PRAS40 was transferred to Beclin1 under hypoxia, resulting in the increase of Beclin1 phosphorylation. These results suggest a novel model of tumorigenesis, in which PGK1 switches between repressing autophagy-mediated cell death via PRAS40 and inducing autophagy through Beclin1 according to the environmental oxygen level. Our study is anticipated to be able to offer novel insights in understanding PGK1/PRAS40 signaling hyperactivated cancers.
Collapse
|
4
|
Morio A, Tsutsumi R, Satomi S, Kondo T, Miyoshi H, Kato T, Kuroda M, Kitamura T, Hara K, Saeki N, Sakaue H, Tsutsumi YM. Leucine imparts cardioprotective effects by enhancing mTOR activity and mitochondrial fusion in a myocardial ischemia/reperfusion injury murine model. Diabetol Metab Syndr 2021; 13:139. [PMID: 34801078 PMCID: PMC8606064 DOI: 10.1186/s13098-021-00755-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 11/04/2021] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Coronary artery disease is a leading cause of morbidity and mortality among patients with diabetes. Previously, we demonstrated that branched-chain amino acids (BCAAs) showed cardioprotective effects against cardiac ischemia/reperfusion (I/R) injury. A recent study suggested that leucine (Leu), a BCAA, is a key amino acid involved in mammalian target of rapamycin (mTOR) activity and mitochondrial function. However, whether Leu has cardioprotective effects on diabetic hearts is unclear. In this study, we examined the preconditioning effect of Leu treatment on high-fat diet (HFD)-induced obese mouse which simulate prediabetic heart. METHODS In vivo mice models of I/R injury were divided into the following groups: control, mTOR+/-, and high-fat diet (HFD)-induced obese groups. Mice were randomly administered with Leu, the mTOR inhibitor rapamycin (Rap), or Leu with Rap. Isolated rat cardiomyocytes were subjected to simulated I/R injury. Biochemical and mitochondrial functional assays were performed to evaluate the changes in mTOR activity and mitochondrial dynamics caused by Leu treatment. RESULTS Leu-treated mice showed a significant reduction in infarct size when compared with the control group (34.8% ± 3.8% vs. 43.1% ± 2.4%, n = 7, p < 0.05), whereas Rap-treated mice did not show the protective effects of Leu. This preconditioning effect of Leu was attenuated in mTOR+/- mice. Additionally, Leu increased the percentage of fused mitochondria and the mitochondrial volume, and decreased the number of mitochondria per cell in isolated cardiomyocytes. In HFD-induced obese mice, Leu treatment significantly reduced infarct size (41.0% ± 1.1% vs. 51.0% ± 1.4%, n = 7, p < 0.05), which was not induced by ischemic preconditioning, and this effect was inhibited by Rap. Furthermore, we observed enhanced mTOR protein expression and mitochondrial fusion with decreased reactive oxygen species production with Leu treatment in HFD-induced obese mice, but not in mTOR+/- mice. CONCLUSIONS Leu treatment improved the damage caused by myocardial I/R injury by promoting mTOR activity and mitochondrial fusion on prediabetic hearts in mice.
Collapse
Affiliation(s)
- Atsushi Morio
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8551, Japan
| | - Rie Tsutsumi
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, 770-8503, Japan
| | - Shiho Satomi
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8551, Japan
| | - Takashi Kondo
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8551, Japan
| | - Hirotsugu Miyoshi
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8551, Japan
| | - Takahiro Kato
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8551, Japan
| | - Masashi Kuroda
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, 770-8503, Japan
| | - Tadahiro Kitamura
- Laboratory of Metabolic Signal, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512, Japan
| | - Kenta Hara
- Kita Harima Medical Center, 926-250 Ichiba, Ono, Hyogo, 675-1392, Japan
| | - Noboru Saeki
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8551, Japan
| | - Hiroshi Sakaue
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, 3-18-15 Kuramoto, Tokushima, 770-8503, Japan
| | - Yasuo M Tsutsumi
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami, Hiroshima, 734-8551, Japan.
| |
Collapse
|
5
|
Morio A, Tsutsumi R, Kondo T, Miyoshi H, Kato T, Narasaki S, Satomi S, Nakaya E, Kuroda M, Sakaue H, Kitamura T, Tsutsumi YM. Leucine induces cardioprotection in vitro by promoting mitochondrial function via mTOR and Opa-1 signaling. Nutr Metab Cardiovasc Dis 2021; 31:2979-2986. [PMID: 34362635 DOI: 10.1016/j.numecd.2021.06.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 01/30/2023]
Abstract
BACKGROUND AND AIMS Coronary heart disease is a major global health concern. Further, severity of this condition is greatly influenced by myocardial ischemia/reperfusion (I/R) injury. Branched-chain amino acids (BCAAs) have cardioprotective effects against I/R via mammalian target of rapamycin (mTOR) activity, wherein Leu is considered to particularly regulate mTOR activation. However, the mechanism underlying cardioprotective effects of Leu via mTOR activity is not fully elucidated. Here, we aimed to study the signaling pathway of cardioprotection and mitochondrial function induced by Leu treatment. METHODS AND RESULTS Cardiac myocytes isolated from adult male Wistar rats were incubated and exposed to simulated I/R (SI/R) injury by replacing the air content. Cardiac myocytes were treated with Leu and subsequently, their survival rate was calculated. To elucidate the signaling pathway and mitochondrial function, immunoblots and mitochondrial permeability transition pore were examined. Cell survival rate was decreased with SI/R but improved by 160 μM Leu (38.5 ± 3.6% vs. 64.5 ± 4.2%, respectively, p < 0.001). Although rapamycin (mTOR inhibitor) prevented this cardioprotective effect induced by Leu, wortmannin (PI3K inhibitor) did not interfere with this effect. In addition, we indicated that overexpression of Opa-1 and mitochondrial function are ameliorated via Leu-induced mitochondrial biogenesis. In contrast, knockdown of Opa-1 suppressed Leu-induced cardioprotection. CONCLUSION Leu treatment is critical in rendering a cardioprotective effect exhibited by BCAAs via mTOR signaling. Furthermore, Leu improved mitochondrial function.
Collapse
Affiliation(s)
- Atsushi Morio
- Department of Anesthesiology and Critical Care, Hiroshima University, Hiroshima, Japan
| | - Rie Tsutsumi
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Takashi Kondo
- Department of Anesthesiology and Critical Care, Hiroshima University, Hiroshima, Japan
| | - Hirotsugu Miyoshi
- Department of Anesthesiology and Critical Care, Hiroshima University, Hiroshima, Japan
| | - Takahiro Kato
- Department of Anesthesiology and Critical Care, Hiroshima University, Hiroshima, Japan
| | - Soshi Narasaki
- Department of Anesthesiology and Critical Care, Hiroshima University, Hiroshima, Japan
| | - Shiho Satomi
- Department of Anesthesiology and Critical Care, Hiroshima University, Hiroshima, Japan
| | - Erika Nakaya
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Masashi Kuroda
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Hiroshi Sakaue
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Tadahiro Kitamura
- Laboratory of Metabolic Signal, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
| | - Yasuo M Tsutsumi
- Department of Anesthesiology and Critical Care, Hiroshima University, Hiroshima, Japan.
| |
Collapse
|
6
|
Bae J, Paltzer WG, Mahmoud AI. The Role of Metabolism in Heart Failure and Regeneration. Front Cardiovasc Med 2021; 8:702920. [PMID: 34336958 PMCID: PMC8322239 DOI: 10.3389/fcvm.2021.702920] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/23/2021] [Indexed: 12/25/2022] Open
Abstract
Heart failure is the leading cause of death worldwide. The inability of the adult mammalian heart to regenerate following injury results in the development of systolic heart failure. Thus, identifying novel approaches toward regenerating the adult heart has enormous therapeutic potential for adult heart failure. Mitochondrial metabolism is an essential homeostatic process for maintaining growth and survival. The emerging role of mitochondrial metabolism in controlling cell fate and function is beginning to be appreciated. Recent evidence suggests that metabolism controls biological processes including cell proliferation and differentiation, which has profound implications during development and regeneration. The regenerative potential of the mammalian heart is lost by the first week of postnatal development when cardiomyocytes exit the cell cycle and become terminally differentiated. This inability to regenerate following injury is correlated with the metabolic shift from glycolysis to fatty acid oxidation that occurs during heart maturation in the postnatal heart. Thus, understanding the mechanisms that regulate cardiac metabolism is key to unlocking metabolic interventions during development, disease, and regeneration. In this review, we will focus on the emerging role of metabolism in cardiac development and regeneration and discuss the potential of targeting metabolism for treatment of heart failure.
Collapse
Affiliation(s)
- Jiyoung Bae
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| | - Wyatt G Paltzer
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| | - Ahmed I Mahmoud
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| |
Collapse
|
7
|
Tandon S, Sarkar S. The S6k/4E-BP mediated growth promoting sub-pathway of insulin signalling cascade is essential to restrict pathogenesis of poly(Q) disorders in Drosophila. Life Sci 2021; 275:119358. [PMID: 33744321 DOI: 10.1016/j.lfs.2021.119358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/19/2021] [Accepted: 03/06/2021] [Indexed: 01/05/2023]
Abstract
Human neurodegenerative polyglutamine [poly(Q)] disorders, such as Huntington's disease (HD) and spinocerebellar ataxias (SCA), are characterised by an abnormal expansion of CAG repeats in the affected gene. The mutated proteins misfold and aggregate to form inclusion bodies that sequester important factors involved in cellular transcription, growth, stress and autophagic response and other essential functions. The insulin signalling pathway has been demonstrated as a major modifier and a potential drug target to ameliorate the poly(Q) mediated neurotoxicity in various model systems. Insulin signalling cascade harbours several downstream sub-pathways, which are synergistically involved in discharging indispensable biological functions such as growth and proliferation, metabolism, autophagy, regulation of cell death pathways etc. Hence, it is difficult to conclude whether the mitigation of poly(Q) neurotoxicity is an accumulative outcome of the insulin cascade, or the result of a specific sub-pathway. For the first time, we report that the ligand binding domain of insulin receptor mediated downstream growth promoting sub-pathway plays the pivotal role in operating the rescue event. We show that the growth promoting activity of insulin cascade is essential to minimize the abundance of inclusion bodies, to restrict neurodegeneration, and to restore the cellular transcriptional balance. Subsequently, we noted the involvement of the mTOR/S6k/4E-BP candidates in mitigating poly(Q) mediated neurotoxicity. Due to the conserved cellular functioning of the insulin cascade across species, and availability of several growth promoting molecules, our results in Drosophila poly(Q) models indicate towards a possibility of designing novel therapeutic strategies to restrict the pathogenesis of devastating human poly(Q) disorders.
Collapse
Affiliation(s)
- Shweta Tandon
- Department of Genetics, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India
| | - Surajit Sarkar
- Department of Genetics, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India.
| |
Collapse
|
8
|
Ahmadi F, Ghanbar Zadeh M, Habibi A, Karimi F. Effect of resistance training with Spirulina platensis on PI3K/Akt/mTOR/p70S6k signaling pathway in cardiac muscle. Sci Sports 2020. [DOI: 10.1016/j.scispo.2019.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
|
9
|
Fidale TM, Antunes HKM, Roever L, Gonçalves A, Puga GM, Silva RPM, de Resende FN, de Souza FR, Fidale BM, Lizardo FB, Resende ES. Leucine Supplementation Improves Effort Tolerance of Rats With Hyperthyroidism. Front Physiol 2018; 9:1632. [PMID: 30524299 PMCID: PMC6256244 DOI: 10.3389/fphys.2018.01632] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 10/29/2018] [Indexed: 12/26/2022] Open
Abstract
Leucine is a regulator of protein metabolism in vivo and information on its action on effort tolerance of both animals and humans with hyperthyroidism is scarce. The objective of the present study was to verify the influence of leucine supplementation on the effort tolerance of Wistar rats with experimental hyperthyroidism. 40 animals were divided into four groups of ten: control (C), hormone (H), leucine (L), and hormone + leucine (HL). Hyperthyroidism was induced by daily administration of 20 μ⋅g100 g-1 of levothyroxine sodium in aqueous suspension by gavage. Leucine was supplemented by adding 5% of the amino acid to the conventional feed. The animals’ blood was collected by cardiac puncture to analyze TSH, T4, and T3 levels. The effort tolerance was determined by the swimming test with a 7% load attached to animals’ tails. Statistical analysis was performed using the Shapiro-Wilk normality test, followed by the analysis of variance (ANOVA) of repeated measures of two factors (treatment × time) and Tukey post hoc, with a significance level of p < 0.05. Administering thyroid hormone increased the swimming performance of rats after 14 and 21 days, but with a drop in performance at 28 days. The HL group, on the other hand, had a significantly higher swimming performance compared to the other groups after 28 days of treatment. Leucine supplementation associated with the experimental model of hyperthyroidism improved the performance of rats in a swimming test after 28 days of treatment.
Collapse
Affiliation(s)
- Thiago Montes Fidale
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil.,Special Academic Unit of Biotechnology, Federal University of Goiás, Catalão, Brazil.,Post-graduate Science in Health, Federal University of Uberlândia, Uberlândia, Brazil
| | | | - Leonardo Roever
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil
| | - Alexandre Gonçalves
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil.,Post-graduate Science in Health, Federal University of Uberlândia, Uberlândia, Brazil.,Master Institute of Education, IMEPAC, Araguari, Brazil
| | - Guilherme Morais Puga
- Faculty of Physical Education, Federal University of Uberlândia, Uberlândia, Brazil.,Post-graduate Science in Health, Federal University of Uberlândia, Uberlândia, Brazil
| | | | | | - Fernanda Rodrigues de Souza
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil.,Post-graduate Science in Health, Federal University of Uberlândia, Uberlândia, Brazil
| | - Beatriz Montes Fidale
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil.,Post-graduate Science in Health, Federal University of Uberlândia, Uberlândia, Brazil
| | | | - Elmiro Santos Resende
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil.,Post-graduate Science in Health, Federal University of Uberlândia, Uberlândia, Brazil
| |
Collapse
|
10
|
Study on Cardiotoxicity and Mechanism of "Fuzi" Extracts Based on Metabonomics. Int J Mol Sci 2018; 19:ijms19113506. [PMID: 30405071 PMCID: PMC6274692 DOI: 10.3390/ijms19113506] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 10/26/2018] [Accepted: 11/05/2018] [Indexed: 01/15/2023] Open
Abstract
To investigate the toxicity of water and ethanol "Fuzi" (FZ) extracts and to explore the toxicity mechanism in rats. Water and ethanol extracts were prepared. Three groups of rats received the water extract, ethanol extract, or water by oral gavage for seven days. Pathological section staining of heart tissue. Colorimetric analysis was used to determine serum lactate dehydrogenase. The metabolic expression of small molecules in rats was measured by a metabolomics method. Western blotting was used to detect the expression of phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), mammalian target of rapamycin (mTOR), transforming growth factor-β1 (TGF-β1), and caspase-3. Immunohistochemistry was used to detect the expression of CTnI, mTOR, and TGF-β1. The water and ethanol FZ extracts exert cardiotoxic effects via activating the PI3K/Akt/mTOR signaling pathway to induce cardiomyocyte apoptosis.
Collapse
|
11
|
Bonvini A, Coqueiro AY, Tirapegui J, Calder PC, Rogero MM. Immunomodulatory role of branched-chain amino acids. Nutr Rev 2018; 76:840-856. [DOI: 10.1093/nutrit/nuy037] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Affiliation(s)
- Andrea Bonvini
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Audrey Y Coqueiro
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Julio Tirapegui
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Philip C Calder
- Human Development and Health Academic Unit, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust and University of Southampton, Southampton, United Kingdom
| | - Marcelo M Rogero
- Department of Nutrition, Faculty of Public Health, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
12
|
Gélinas R, Mailleux F, Dontaine J, Bultot L, Demeulder B, Ginion A, Daskalopoulos EP, Esfahani H, Dubois-Deruy E, Lauzier B, Gauthier C, Olson AK, Bouchard B, Des Rosiers C, Viollet B, Sakamoto K, Balligand JL, Vanoverschelde JL, Beauloye C, Horman S, Bertrand L. AMPK activation counteracts cardiac hypertrophy by reducing O-GlcNAcylation. Nat Commun 2018; 9:374. [PMID: 29371602 PMCID: PMC5785516 DOI: 10.1038/s41467-017-02795-4] [Citation(s) in RCA: 171] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 12/28/2017] [Indexed: 12/11/2022] Open
Abstract
AMP-activated protein kinase (AMPK) has been shown to inhibit cardiac hypertrophy. Here, we show that submaximal AMPK activation blocks cardiomyocyte hypertrophy without affecting downstream targets previously suggested to be involved, such as p70 ribosomal S6 protein kinase, calcineurin/nuclear factor of activated T cells (NFAT) and extracellular signal-regulated kinases. Instead, cardiomyocyte hypertrophy is accompanied by increased protein O-GlcNAcylation, which is reversed by AMPK activation. Decreasing O-GlcNAcylation by inhibitors of the glutamine:fructose-6-phosphate aminotransferase (GFAT), blocks cardiomyocyte hypertrophy, mimicking AMPK activation. Conversely, O-GlcNAcylation-inducing agents counteract the anti-hypertrophic effect of AMPK. In vivo, AMPK activation prevents myocardial hypertrophy and the concomitant rise of O-GlcNAcylation in wild-type but not in AMPKα2-deficient mice. Treatment of wild-type mice with O-GlcNAcylation-inducing agents reverses AMPK action. Finally, we demonstrate that AMPK inhibits O-GlcNAcylation by mainly controlling GFAT phosphorylation, thereby reducing O-GlcNAcylation of proteins such as troponin T. We conclude that AMPK activation prevents cardiac hypertrophy predominantly by inhibiting O-GlcNAcylation.
Collapse
Affiliation(s)
- Roselle Gélinas
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Florence Mailleux
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Justine Dontaine
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Laurent Bultot
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Bénédicte Demeulder
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Audrey Ginion
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Evangelos P Daskalopoulos
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Hrag Esfahani
- Pole of Pharmacotherapy, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Emilie Dubois-Deruy
- Pole of Pharmacotherapy, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Benjamin Lauzier
- l'institut du thorax, INSERM, CNRS, Univ. Nantes, Nantes, 44007, France
| | - Chantal Gauthier
- l'institut du thorax, INSERM, CNRS, Univ. Nantes, Nantes, 44007, France
| | - Aaron K Olson
- Department of Pediatrics, University of Washington School of Medicine and Seattle Children's Research Institute, Seattle, 98105-0371, WA, USA.,Montreal Heart Institute, Montreal, H1T 1C8, Canada
| | | | - Christine Des Rosiers
- Montreal Heart Institute, Montreal, H1T 1C8, Canada.,Department of Nutrition, Université de Montréal, Montreal, H3T 1A8, Canada
| | - Benoit Viollet
- Institut Cochin, INSERM U1016, 75014, Paris, France.,CNRS UMR8104, 75014, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, 75014, France
| | - Kei Sakamoto
- Nestlé Institute of Health Sciences SA, Lausanne, 1015, Switzerland
| | - Jean-Luc Balligand
- Pole of Pharmacotherapy, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Jean-Louis Vanoverschelde
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium.,Division of Cardiology, Cliniques Universitaires Saint-Luc, Brussels, 1200, Belgium
| | - Christophe Beauloye
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium.,Division of Cardiology, Cliniques Universitaires Saint-Luc, Brussels, 1200, Belgium
| | - Sandrine Horman
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Luc Bertrand
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium.
| |
Collapse
|
13
|
Fidale TM, Antunes HKM, Alex Dos Santos L, Rodrigues de Souza F, Deconte SR, Borges Rosa de Moura F, Mantovani MM, Alves Duarte PR, Roever L, Resende ES. Increased Dietary Leucine Reduces Doxorubicin-Associated Cardiac Dysfunction in Rats. Front Physiol 2018; 8:1042. [PMID: 29403386 PMCID: PMC5779071 DOI: 10.3389/fphys.2017.01042] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 11/29/2017] [Indexed: 01/01/2023] Open
Abstract
Cardiotoxicity is one of the most significant adverse effects of the oncologic treatment with doxorubicin, which is responsible for a substantial morbid and mortality. The occurrence of heart failure with ventricular dysfunction may lead to severe cardiomyopathy and ultimately to death. Studies have focused on the effects of leucine supplementation as a strategy to minimize or revert the clinical condition of induced proteolysis by several clinical onsets. However, the impact of leucine supplementation in heart failure induced by doxorubicin is unknown. Therefore, the objective of this work is to evaluate the effects of leucine supplementation on the cardiotoxicity in the heart of rats treated with doxorubicin. Rats treated with a 7.5 mg/kg cumulative dose of doxorubicin for 14 days presented a dilatation of the left ventricle (LV), and a reduction of the ejection fraction (FE). The 5% supplementation of leucine in the rats' food prevented the malfunctioning of the LV when administered with doxorubicin. Some alterations in the extracellular matrix remodeling were confirmed by the increase of collagen fibers in the doxorubicin group, which did not increase when the treatment was associated with leucine supplementation. Leucine attenuates heart failure in this experimental model with doxorubicin. Such protection is followed by the maintenance of interstitial collagen fibers.
Collapse
Affiliation(s)
- Thiago M Fidale
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil
| | - Hanna K M Antunes
- Department of Bioscience, Federal University of São Paulo, São Paulo, Brazil
| | | | | | - Simone R Deconte
- Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Brazil
| | | | | | | | - Leonardo Roever
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil
| | - Elmiro S Resende
- Laboratory of Experimental Medicine, Federal University of Uberlândia, Uberlândia, Brazil
| |
Collapse
|
14
|
Orlacchio A, Ranieri M, Brave M, Arciuch VA, Forde T, De Martino D, Anderson KE, Hawkins P, Di Cristofano A. SGK1 Is a Critical Component of an AKT-Independent Pathway Essential for PI3K-Mediated Tumor Development and Maintenance. Cancer Res 2017; 77:6914-6926. [PMID: 29055016 DOI: 10.1158/0008-5472.can-17-2105] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 09/12/2017] [Accepted: 10/17/2017] [Indexed: 02/06/2023]
Abstract
Activation of the PI3K-AKT signaling cascade is a common critical event during malignant transformation. In this study, we used thyroid gland epithelial cells and a series of genetically engineered mouse strains as model systems to demonstrate that, although necessary, AKT activation is not sufficient for PI3K-driven transformation. Instead, transformation requires the activity of the PDK1-regulated AGC family of protein kinases. In particular, SGK1 was found to be essential for proliferation and survival of thyroid cancer cells harboring PI3K-activating mutations. Notably, cotargeting SGK1 and AKT resulted in significantly higher growth suppression than inhibiting either PI3K or AKT alone. Overall, these findings underscore the clinical relevance of AKT-independent pathways in tumors driven by genetic lesions targeting the PI3K cascade. Cancer Res; 77(24); 6914-26. ©2017 AACR.
Collapse
Affiliation(s)
- Arturo Orlacchio
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Michela Ranieri
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Martina Brave
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Valeria Antico Arciuch
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Toni Forde
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Daniela De Martino
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Karen E Anderson
- Inositide Laboratory, Babraham Institute, Babraham, Cambridge, United Kingdom
| | - Phillip Hawkins
- Inositide Laboratory, Babraham Institute, Babraham, Cambridge, United Kingdom
| | - Antonio Di Cristofano
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York.
| |
Collapse
|
15
|
Chen GM, Zheng AJ, Cai J, Han P, Ji HB, Wang LL. microRNA-145-3p inhibits non-small cell lung cancer cell migration and invasion by targeting PDK1 via the mTOR signaling pathway. J Cell Biochem 2017; 119:885-895. [PMID: 28661070 DOI: 10.1002/jcb.26252] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/28/2017] [Indexed: 12/12/2022]
Abstract
The mammalian target of rapamycin (mTOR) pathway is dysregulated in more than 50% of all human malignancies and is a major target in cancer treatment. In this study, we explored the underlying mechanism involving microRNA-145-3p (miR-145-3p) in the development and progression of non-small cell lung cancer (NSCLC) by targeting PDK1 via the mTOR signaling pathway. NSCLC tissues and adjacent normal tissues were obtained from 83 NSCLC patients. miR-145-3p, PDK1, and mTOR levels were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Human NSCLC cell lines A549 and H1299 were transfected with miR-145-3p and siPDK1 to confirm the effect of miR-145-3p and PDK1 on NSCLC cells in vitro. Cell growth was evaluated by a CCK8 assay. Cell motility and chemotaxis analysis were determined by the scratch test and chemotaxis assay, respectively. The protein levels of PDK1 and mTOR were measured using the western blotting. Results showed lower level of miR-145-3p and higher levels of PDK1 and mTOR in NSCLC tissues compared to the adjacent normal tissues. In vitro results showed that cell growth, cell motility, and chemotaxis were all inhibited in cells transfected with miR-145-3p and those transfected with siPDK. Additionally, dual luciferase reporter gene assay helped confirmed that PDK1 is a target of miR-145. Finally, levels of PDK1, mTOR, and phosphorylated-mTOR were lower in cells transfected with miR-145-3p as well as those with siPDK1. These findings indicate that miR-145-3p may inhibit cell growth, motility, and chemotaxis in NSCLC by targeting PDK1 through suppressing the mTOR pathway.
Collapse
Affiliation(s)
- Gui-Min Chen
- Department of Oncology, Linyi Cancer Hospital, Linyi, P. R. China
| | - A-Juan Zheng
- Department of Imaging, Linyi People's Hospital, Linyi, P. R. China
| | - Jing Cai
- Department of Neurosurgery, Linyi People's Hospital, Linyi, P. R. China
| | - Ping Han
- Department of Respiratory Medicine, Linyi People's Hospital, Linyi, P. R. China
| | - Hong-Bo Ji
- Department of Medical Oncology in Section One, Inner Mongolia Chifeng Hospital, Chifeng, P. R. China
| | - Le-Le Wang
- Department of Medical Oncology in Section One, Inner Mongolia Chifeng Hospital, Chifeng, P. R. China
| |
Collapse
|
16
|
D'Abronzo LS, Bose S, Crapuchettes ME, Beggs RE, Vinall RL, Tepper CG, Siddiqui S, Mudryj M, Melgoza FU, Durbin-Johnson BP, deVere White RW, Ghosh PM. The androgen receptor is a negative regulator of eIF4E phosphorylation at S209: implications for the use of mTOR inhibitors in advanced prostate cancer. Oncogene 2017; 36:6359-6373. [PMID: 28745319 PMCID: PMC5690844 DOI: 10.1038/onc.2017.233] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 05/22/2017] [Accepted: 06/06/2017] [Indexed: 01/25/2023]
Abstract
The anti-androgen bicalutamide is widely used in the treatment of advanced prostate cancer (PCa) in many countries, but its effect on castration resistant PCa (CRPC) is limited. We previously showed that resistance to bicalutamide results from activation of mechanistic target of rapamycin (mTOR). Interestingly, clinical trials testing combinations of the mTOR inhibitor RAD001 with bicalutamide were effective in bicalutamide-naïve CRPC patients, but not in bicalutamide-pre-treated ones. Here we investigate causes for their difference in response. Evaluation of CRPC cell lines identified resistant vs sensitive in-vitro models, and revealed that increased eIF4E(S209) phosphorylation is associated with resistance to the combination. We confirmed using a human-derived tumor-xenograft mouse model that bicalutamide pre-treatment is associated with an increase in eIF4E(S209) phosphorylation. Thus, AR suppressed eIF4E phosphorylation, while the use of anti-androgens relieved this suppression, thereby triggering its increase. Additional investigation in human prostatectomy samples showed that increased eIF4E phosphorylation strongly correlated with the cell proliferation marker Ki67. SiRNA-mediated knock-down of eIF4E sensitized CRPC cells to RAD001+bicalutamide, while eIF4E overexpression induced resistance. Inhibition of eIF4E phosphorylation by treatment with CGP57380 (an inhibitor of MAPK interacting serine-threonine kinases Mnk1/2, the eIF4E upstream kinase) or inhibitors of ERK1/2, the upstream kinase regulating Mnk1/2, also sensitized CRPC cells to RAD001+bicalutamide. Examination of downstream targets of eIF4E-mediated translation, including survivin, demonstrated that eIF4E(S209) phosphorylation increased cap-independent translation whereas its inhibition restored cap-dependent translation which could be inhibited by mTOR inhibitors. Thus, our results demonstrate that while combinations of AR and mTOR inhibitors were effective in suppressing tumor growth by inhibiting both AR-induced transcription and mTOR-induced cap-dependent translation, pre-treatment with AR antagonists including bicalutamide increased eIF4E phosphorylation that induced resistance to combinations of AR and mTOR inhibitors by inducing cap-independent translation. We conclude that this resistance can be overcome by inhibiting eIF4E phosphorylation with Mnk1/2 or ERK1/2 inhibitors.
Collapse
Affiliation(s)
- L S D'Abronzo
- VA Northern California Health Care System, University of California at Davis, Sacramento, CA, USA.,Department of Urology, University of California Davis School of Medicine, University of California at Davis, Sacramento, CA, USA
| | - S Bose
- Department of Urology, University of California Davis School of Medicine, University of California at Davis, Sacramento, CA, USA
| | - M E Crapuchettes
- VA Northern California Health Care System, University of California at Davis, Sacramento, CA, USA
| | - R E Beggs
- VA Northern California Health Care System, University of California at Davis, Sacramento, CA, USA
| | - R L Vinall
- Department of Urology, University of California Davis School of Medicine, University of California at Davis, Sacramento, CA, USA.,California Northstate University College of Pharmacy, Elk Grove, CA, USA
| | - C G Tepper
- Department of Biochemistry and Molecular Medicine, University of California at Davis, Sacramento, CA, USA
| | - S Siddiqui
- VA Northern California Health Care System, University of California at Davis, Sacramento, CA, USA
| | - M Mudryj
- Department of Medical Microbiology and Immunology, University of California at Davis, Sacramento, CA, USA
| | - F U Melgoza
- VA Northern California Health Care System, University of California at Davis, Sacramento, CA, USA
| | - B P Durbin-Johnson
- Department of Public Health, Division of Biostatistics, University of California at Davis, Sacramento, CA, USA
| | - R W deVere White
- Department of Urology, University of California Davis School of Medicine, University of California at Davis, Sacramento, CA, USA
| | - P M Ghosh
- VA Northern California Health Care System, University of California at Davis, Sacramento, CA, USA.,Department of Urology, University of California Davis School of Medicine, University of California at Davis, Sacramento, CA, USA.,Department of Biochemistry and Molecular Medicine, University of California at Davis, Sacramento, CA, USA
| |
Collapse
|
17
|
Renguet E, Ginion A, Gélinas R, Bultot L, Auquier J, Robillard Frayne I, Daneault C, Vanoverschelde JL, Des Rosiers C, Hue L, Horman S, Beauloye C, Bertrand L. Metabolism and acetylation contribute to leucine-mediated inhibition of cardiac glucose uptake. Am J Physiol Heart Circ Physiol 2017. [PMID: 28646031 DOI: 10.1152/ajpheart.00738.2016] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
High plasma leucine levels strongly correlate with type 2 diabetes. Studies of muscle cells have suggested that leucine alters the insulin response for glucose transport by activating an insulin-negative feedback loop driven by the mammalian target of rapamycin/p70 ribosomal S6 kinase (mTOR/p70S6K) pathway. Here, we examined the molecular mechanism involved in leucine's action on cardiac glucose uptake. Leucine was indeed able to curb glucose uptake after insulin stimulation in both cultured cardiomyocytes and perfused hearts. Although leucine activated mTOR/p70S6K, the mTOR inhibitor rapamycin did not prevent leucine's inhibitory action on glucose uptake, ruling out the contribution of the insulin-negative feedback loop. α-Ketoisocaproate, the first metabolite of leucine catabolism, mimicked leucine's effect on glucose uptake. Incubation of cardiomyocytes with [13C]leucine ascertained its metabolism to ketone bodies (KBs), which had a similar negative impact on insulin-stimulated glucose transport. Both leucine and KBs reduced glucose uptake by affecting translocation of glucose transporter 4 (GLUT4) to the plasma membrane. Finally, we found that leucine elevated the global protein acetylation level. Pharmacological inhibition of lysine acetyltransferases counteracted this increase in protein acetylation and prevented leucine's inhibitory action on both glucose uptake and GLUT4 translocation. Taken together, these results indicate that leucine metabolism into KBs contributes to inhibition of cardiac glucose uptake by hampering the translocation of GLUT4-containing vesicles via acetylation. They offer new insights into the establishment of insulin resistance in the heart.NEW & NOTEWORTHY Catabolism of the branched-chain amino acid leucine into ketone bodies efficiently inhibits cardiac glucose uptake through decreased translocation of glucose transporter 4 to the plasma membrane. Leucine increases protein acetylation. Pharmacological inhibition of acetylation reverses leucine's action, suggesting acetylation involvement in this phenomenon.Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/leucine-metabolism-inhibits-cardiac-glucose-uptake/.
Collapse
Affiliation(s)
- Edith Renguet
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | - Audrey Ginion
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | - Roselle Gélinas
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | - Laurent Bultot
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | - Julien Auquier
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | | | | | - Jean-Louis Vanoverschelde
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium.,Cliniques Universitaires Saint-Luc, Division of Cardiology, Brussels, Belgium
| | - Christine Des Rosiers
- Montreal Heart Institute, Montreal, Quebec, Canada.,Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada; and
| | - Louis Hue
- Université catholique de Louvain, de Duve Institute, Brussels, Belgium
| | - Sandrine Horman
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | - Christophe Beauloye
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium.,Cliniques Universitaires Saint-Luc, Division of Cardiology, Brussels, Belgium
| | - Luc Bertrand
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium;
| |
Collapse
|
18
|
Kim H, Kim DH, Jeong B, Kim JH, Lee SR, Sonn JK. Blebbistatin induces chondrogenesis of single mesenchymal cells via PI3K/PDK1/mTOR/p70S6K pathway. Biologia (Bratisl) 2017. [DOI: 10.1515/biolog-2017-0078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
19
|
Lv D, Guo L, Zhang T, Huang L. PRAS40 signaling in tumor. Oncotarget 2017; 8:69076-69085. [PMID: 28978182 PMCID: PMC5620322 DOI: 10.18632/oncotarget.17299] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/11/2017] [Indexed: 12/11/2022] Open
Abstract
The proline-rich Akt substrate of 40 kDa (PRAS40) is a substrate of Akt and a component of the mammalian target of rapamycin complex 1 (mTORC1). Locating at the crossroad of the PI3K/Akt pathway and the mTOR pathway, PRAS40 is phosphorylated by growth factors or other stimuli, and regulates the activation of these signaling pathways in turn. PRAS40 plays an important role in metabolic disorders and multiple cancers, and the phosphorylation of PRAS40 is often associated with the tumor progression of melanoma, prostate cancer, etc. PRAS40 promotes tumorigenesis by deregulating cellular proliferation, apoptosis, senescence, metastasis, etc. Herein, we provide an overview on current understandings of PRAS40 signaling in the tumor formation and progression, which suggests that PRAS40 or phospho-PRAS40 could become a novel biomarker and therapeutic target in tumor.
Collapse
Affiliation(s)
- Dan Lv
- Department of Pathophysiology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| | - Lianying Guo
- Department of Pathophysiology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| | - Ting Zhang
- Department of Pathophysiology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| | - Lin Huang
- Department of Pathophysiology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China
| |
Collapse
|
20
|
A systems study reveals concurrent activation of AMPK and mTOR by amino acids. Nat Commun 2016; 7:13254. [PMID: 27869123 PMCID: PMC5121333 DOI: 10.1038/ncomms13254] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 09/13/2016] [Indexed: 12/17/2022] Open
Abstract
Amino acids (aa) are not only building blocks for proteins, but also signalling molecules, with the mammalian target of rapamycin complex 1 (mTORC1) acting as a key mediator. However, little is known about whether aa, independently of mTORC1, activate other kinases of the mTOR signalling network. To delineate aa-stimulated mTOR network dynamics, we here combine a computational–experimental approach with text mining-enhanced quantitative proteomics. We report that AMP-activated protein kinase (AMPK), phosphatidylinositide 3-kinase (PI3K) and mTOR complex 2 (mTORC2) are acutely activated by aa-readdition in an mTORC1-independent manner. AMPK activation by aa is mediated by Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ). In response, AMPK impinges on the autophagy regulators Unc-51-like kinase-1 (ULK1) and c-Jun. AMPK is widely recognized as an mTORC1 antagonist that is activated by starvation. We find that aa acutely activate AMPK concurrently with mTOR. We show that AMPK under aa sufficiency acts to sustain autophagy. This may be required to maintain protein homoeostasis and deliver metabolite intermediates for biosynthetic processes. mTORC1 is known to mediate the signalling activity of amino acids. Here, the authors combine modelling with experiments and find that amino acids acutely stimulate mTORC2, IRS/PI3K and AMPK, independently of mTORC1. AMPK activation through CaMKKβ sustains autophagy under non-starvation conditions.
Collapse
|
21
|
Su T, Tan Y, Tsui MS, Yi H, Fu XQ, Li T, Chan CL, Guo H, Li YX, Zhu PL, Tse AKW, Cao H, Lu AP, Yu ZL. Metabolomics reveals the mechanisms for the cardiotoxicity of Pinelliae Rhizoma and the toxicity-reducing effect of processing. Sci Rep 2016; 6:34692. [PMID: 27698376 PMCID: PMC5048190 DOI: 10.1038/srep34692] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/19/2016] [Indexed: 12/28/2022] Open
Abstract
Pinelliae Rhizoma (PR) is a commonly used Chinese medicinal herb, but it has been frequently reported about its toxicity. According to the traditional Chinese medicine theory, processing can reduce the toxicity of the herbs. Here, we aim to determine if processing reduces the toxicity of raw PR, and to explore the underlying mechanisms of raw PR-induced toxicities and the toxicity-reducing effect of processing. Biochemical and histopathological approaches were used to evaluate the toxicities of raw and processed PR. Rat serum metabolites were analyzed by LC-TOF-MS. Ingenuity pathway analysis of the metabolomics data highlighted the biological pathways and network functions involved in raw PR-induced toxicities and the toxicity-reducing effect of processing, which were verified by molecular approaches. Results showed that raw PR caused cardiotoxicity, and processing reduced the toxicity. Inhibition of mTOR signaling and activation of the TGF-β pathway contributed to raw PR-induced cardiotoxicity, and free radical scavenging might be responsible for the toxicity-reducing effect of processing. Our data shed new light on the mechanisms of raw PR-induced cardiotoxicity and the toxicity-reducing effect of processing. This study provides scientific justifications for the traditional processing theory of PR, and should help in optimizing the processing protocol and clinical combinational application of PR.
Collapse
Affiliation(s)
- Tao Su
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Yong Tan
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Science, Beijing, China
| | - Man-Shan Tsui
- Department of Pathology, Caritas Medical Center, Hong Kong, China
| | - Hua Yi
- Department of Pathology, Guangzhou University of Chinese Medicine, China
| | - Xiu-Qiong Fu
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Ting Li
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Chi Leung Chan
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Hui Guo
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Ya-Xi Li
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Pei-Li Zhu
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Anfernee Kai Wing Tse
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
- Institute of Integrated Bioinfomedicine & Translational Science, HKBU Shenzhen Research Institute and Continuing Education, Shenzhen, China
| | - Hui Cao
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Ai-Ping Lu
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
- Institute of Integrated Bioinfomedicine & Translational Science, HKBU Shenzhen Research Institute and Continuing Education, Shenzhen, China
| | - Zhi-Ling Yu
- Consun Chinese Medicines Research Centre for Renal Diseases, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
- Institute of Integrated Bioinfomedicine & Translational Science, HKBU Shenzhen Research Institute and Continuing Education, Shenzhen, China
| |
Collapse
|
22
|
Boutry C, El-Kadi SW, Suryawan A, Steinhoff-Wagner J, Stoll B, Orellana RA, Nguyen HV, Kimball SR, Fiorotto ML, Davis TA. Pulsatile delivery of a leucine supplement during long-term continuous enteral feeding enhances lean growth in term neonatal pigs. Am J Physiol Endocrinol Metab 2016; 310:E699-E713. [PMID: 26884386 PMCID: PMC4835946 DOI: 10.1152/ajpendo.00479.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 02/09/2016] [Indexed: 01/06/2023]
Abstract
Neonatal pigs are used as a model to study and optimize the clinical treatment of infants who are unable to maintain oral feeding. Using this model, we have shown previously that pulsatile administration of leucine during continuous feeding over 24 h via orogastric tube enhanced protein synthesis in skeletal muscle compared with continuous feeding alone. To determine the long-term effects of leucine pulses, neonatal piglets (n = 11-12/group) were continuously fed formula via orogastric tube for 21 days, with an additional parenteral infusion of either leucine (CON + LEU; 800 μmol·kg-1·h-1) or alanine (CON + ALA) for 1 h every 4 h. The results show that body and muscle weights and lean gain were ∼25% greater, and fat gain was 48% lower in CON + LEU than CON + ALA; weights of other tissues were unaffected by treatment. Fractional protein synthesis rates in longissimus dorsi, gastrocnemius, and soleus muscles were ∼30% higher in CON + LEU compared with CON + ALA and were associated with decreased Deptor abundance and increased mTORC1, mTORC2, 4E-BP1, and S6K1 phosphorylation, SNAT2 abundance, and association of eIF4E with eIF4G and RagC with mTOR. There were no treatment effects on PKB, eIF2α, eEF2, or PRAS40 phosphorylation, Rheb, SLC38A9, v-ATPase, LAMTOR1, LAMTOR2, RagA, RagC, and LAT1 abundance, the proportion of polysomes to nonpolysomes, or the proportion of mRNAs encoding rpS4 or rpS8 associated with polysomes. Our results demonstrate that pulsatile delivery of a leucine supplement during 21 days of continuous enteral feeding enhances lean growth by stimulating the mTORC1-dependent translation initiation pathway, leading to protein synthesis in skeletal muscle of neonates.
Collapse
Affiliation(s)
- Claire Boutry
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Samer W El-Kadi
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Agus Suryawan
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Julia Steinhoff-Wagner
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Barbara Stoll
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Renán A Orellana
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Hanh V Nguyen
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Scot R Kimball
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Marta L Fiorotto
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Teresa A Davis
- United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| |
Collapse
|
23
|
Noh J, Wende AR, Olsen CD, Kim B, Bevins J, Zhu Y, Zhang QJ, Riehle C, Abel ED. Phosphoinositide dependent protein kinase 1 is required for exercise-induced cardiac hypertrophy but not the associated mitochondrial adaptations. J Mol Cell Cardiol 2015; 89:297-305. [PMID: 26476238 DOI: 10.1016/j.yjmcc.2015.10.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/28/2015] [Accepted: 10/12/2015] [Indexed: 01/17/2023]
Abstract
Phosphoinositide-dependent protein kinase-1 (PDPK1) is an important mediator of phosphatidylinositol 3-kinase (PI3K) signaling. We previously reported that PI3K but not Akt signaling mediates the increase in mitochondrial oxidative capacity following physiological cardiac hypertrophy. To determine if PDPK1 regulates these metabolic adaptations we examined mice with cardiomyocyte-specific heterozygous knockout of PDPK1 (cPDPK1(+/-)) after 5 wk. exercise swim training. Akt phosphorylation at Thr308 increased by 43% in wildtype (WT) mice but not in cPDPK1(+/-) mice following exercise training. Ventricular contractile function was not different between WT and cPDPK1(+/-) mice at baseline. In addition, exercise did not influence ventricular function in WT or cPDPK1(+/-) mice. Heart weight normalized to tibia length ratios increased by 13.8% in WT mice (6.2±0.2 vs. 7.1±0.2, P=0.001), but not in cPDPK1(+/-) (6.2±0.3 vs. 6.5±0.2, P=0.20) mice after swim training. Diastolic LV dimension increased in WT mice (3.7±0.1 vs. 4.0±0.1 mm, P=0.01) but not in cPDPK1(+/-) (3.8±0.1 vs. 3.7±0.1 mm, P=0.56) following swim training. Maximal mitochondrial oxygen consumption (VADP, nmol/min/mg) using palmitoyl carnitine as a substrate was significantly increased in mice of all genotypes following swim training (WT: 13.6±0.6 vs.16.1±0.9, P=0.04; cPDPK1(+/-): 12.4±0.6 vs.15.9±1.2, P=0.04). These findings suggest that PDPK1 is required for exercise-induced cardiac hypertrophy but does not contribute to exercise-induced increases in mitochondrial function.
Collapse
Affiliation(s)
- Junghyun Noh
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Division of Endocrinology and Metabolism, College of Medicine, Inje University, Goyang, South Korea
| | - Adam R Wende
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Curtis D Olsen
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Bumjun Kim
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Jack Bevins
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Yi Zhu
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Touchstone Diabetes Center, University of Texas Southwestern, Dallas, TX 75390, USA
| | - Quan-Jiang Zhang
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Fraternal Order of Eagles Diabetes Research Center and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Christian Riehle
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Hannover Medical School, Department of Cardiology and Angiology, Carl-Neuberg-Str., 130625 Hannover, Germany
| | - E Dale Abel
- Program in Molecular Medicine and Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Fraternal Order of Eagles Diabetes Research Center and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
| |
Collapse
|
24
|
Han B, Cai H, Chen Y, Hu B, Luo H, Wu Y, Wu J. The role of TGFBI (βig-H3) in gastrointestinal tract tumorigenesis. Mol Cancer 2015; 14:64. [PMID: 25889002 PMCID: PMC4435624 DOI: 10.1186/s12943-015-0335-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 03/09/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND TGFβ-induced (TGFBI/βig-H3) is a protein inducible by TGFβ1 and secreted by many types of cells. It binds to collagen, forms part of the extracellular matrix (ECM), and interacts with integrins on cell surfaces. In this study, we investigated the role of TGFBI in tumorigenesis and the underlying mechanisms. METHODS Patient serum TGFBI levels were determined by ELISA. TGFBI transgenic and gene knockout mice and TGFBI-overexpressing liver cells were used for mechanistic studies. RESULTS We demonstrated that patients with cholangiocarcinomas, hepatic carcinomas or gastric carcinomas presented significantly elevated serum TGFBI levels, and the excess TGFBI was derived from the tumor masses. TGFBI overexpression in mice resulted in increased incidence of spontaneous tumors and N,N-diethylnitrosamine (DEN)-induced liver tumor nodules, compared to that in wild type (WT) mice, while TGFBI knockout mice were comparable to WT controls in these 2 aspects. TGFBI promoted the survival of Aml-12 liver cells with DNA damage after irradiation, and augmented their post-irradiation proliferation. It activated the FAK/AKT/AKT1S1/PRS6/EIF4EBP pathway, which is known to modulate cell survival and proliferation. CONCLUSIONS Our data suggest that TGFBI functions as a promoter of certain gastrointestinal tract cancers. It provides a survival advantage to cells with DNA damage. Over a long time span, this advantage could translate into increased tumor risks.
Collapse
Affiliation(s)
- Bing Han
- Laboratory of Immunology and Cardiovascular Research, Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Stain-Denis Street, Montreal, Quebec, Canada.
| | - Haolei Cai
- Department of Surgery, The Second Affiliated Hospital of Zhejiang University, 88 Jiefang Road, Hangzhou, China.
| | - Ying Chen
- Department of Surgery, The Second Affiliated Hospital of Zhejiang University, 88 Jiefang Road, Hangzhou, China.
| | - Bing Hu
- Anatomic Pathology, AmeriPath Central Florida, 8150 Chancellor Dr, Orlando, FL, USA.
| | - Hongyu Luo
- Laboratory of Immunology and Cardiovascular Research, Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Stain-Denis Street, Montreal, Quebec, Canada.
| | - Yulian Wu
- Department of Surgery, The Second Affiliated Hospital of Zhejiang University, 88 Jiefang Road, Hangzhou, China.
| | - Jiangping Wu
- Laboratory of Immunology and Cardiovascular Research, Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Stain-Denis Street, Montreal, Quebec, Canada. .,Nephrology Service, Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Stain-Denis Street, Montreal, Quebec, Canada.
| |
Collapse
|
25
|
Timmermans AD, Balteau M, Gélinas R, Renguet E, Ginion A, de Meester C, Sakamoto K, Balligand JL, Bontemps F, Vanoverschelde JL, Horman S, Beauloye C, Bertrand L. A-769662 potentiates the effect of other AMP-activated protein kinase activators on cardiac glucose uptake. Am J Physiol Heart Circ Physiol 2014; 306:H1619-30. [PMID: 24748590 DOI: 10.1152/ajpheart.00965.2013] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
AMP-activated protein kinase (AMPK), a key cellular sensor of energy, regulates metabolic homeostasis and plays a protective role in the ischemic or diabetic heart. Stimulation of cardiac glucose uptake contributes to this AMPK-mediated protection. The small-molecule AMPK activator A-769662, which binds and directly activates AMPK, has recently been characterized. A-769662-dependent AMPK activation protects the heart against an ischemia-reperfusion episode but is unable to stimulate skeletal muscle glucose uptake. Here, we tried to reconcile these conflicting findings by investigating the impact of A-769662 on cardiac AMPK signaling and glucose uptake. We showed that A-769662 promoted AMPK activation, resulting in the phosphorylation of several downstream targets, but was incapable of stimulating glucose uptake in cultured cardiomyocytes and the perfused heart. The lack of glucose uptake stimulation can be explained by A-769662's narrow specificity, since it selectively activates cardiac AMPK heterotrimeric complexes containing α2/β1-subunits, the others being presumably required for this metabolic outcome. However, when combined with classical AMPK activators, such as metformin, phenformin, oligomycin, or hypoxia, which impact AMPK heterotrimers more broadly via elevation of cellular AMP levels, A-769662 induced more profound AMPK phosphorylation and subsequent glucose uptake stimulation. The synergistic effect of A-769662 under such ischemia-mimetic conditions protected cardiomyocytes against ROS production and cell death. In conclusion, despite the fact that A-769662 activates AMPK, it alone does not significantly stimulate glucose uptake. However, strikingly, its ability of potentiating the action on other AMPK activators makes it a potentially useful participant in the protective role of AMPK in the heart.
Collapse
Affiliation(s)
- Aurélie D Timmermans
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Magali Balteau
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Roselle Gélinas
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Edith Renguet
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Audrey Ginion
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Carole de Meester
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Kei Sakamoto
- Medical Research Council Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Jean-Luc Balligand
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Pharmacology and Therapeutics, Brussels, Belgium; and
| | | | - Jean-Louis Vanoverschelde
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Sandrine Horman
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Christophe Beauloye
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium
| | - Luc Bertrand
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pôle de Recherche Cardiovasculaire, Brussels, Belgium;
| |
Collapse
|
26
|
Han B, Luo H, Raelson J, Huang J, Li Y, Tremblay J, Hu B, Qi S, Wu J. TGFBI (βIG-H3) is a diabetes-risk gene based on mouse and human genetic studies. Hum Mol Genet 2014; 23:4597-611. [PMID: 24728038 DOI: 10.1093/hmg/ddu173] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Transforming growth factor beta-induced (TGFBI/βIG-H3), also known as βig-H3, is a protein inducible by TGFβ1 and secreted by many cell types. It binds to collagen, forms part of the extracellular matrix and interacts with integrins on the cell surface. Recombinant TGFBI and transgenic TGFBI overexpression can promote both islet survival and function. In this study, we generated TGFBI KO mice and further assessed TGFBI function and signaling pathways in islets. Islets from KO mice were of normal size and quantity, and these animals were normoglycemic. However, KO islet survival and function was compromised in vitro. In vivo, KO donor islets became inferior to wild-type donor islets in achieving normoglycemia when transplanted into KO diabetic recipients. TGFBI KO mice were more prone to straptozotocin-induced diabetes than the wild-type counterpart. Phosphoprotein array analysis established that AKT1S1, a molecule linking the AKT and mTORC1 signaling pathways, was modulated by TGFBI in islets. Phosphorylation of four molecules in the AKT and mTORC1 signaling pathway, i.e. AKT, AKT1S1, RPS6 and EIF4EBP1, was upregulated in islets upon TGFBI stimulation. Suppression of AKT activity by a chemical inhibitor, or knockdown of AKT1S1, RPS6 and EIF4EBP1 expression by small interfering RNA, modulated islet survival, proving the relevance of these molecules in TGFBI-triggered signaling. Human genetic studies revealed that in the TGFBI gene and its vicinity, three single-nucleotide polymorphisms were significantly associated with type 1 diabetes risks, and one with type 2 diabetes risks. Our study suggests that TGFBI is a potential risk gene for human diabetes.
Collapse
Affiliation(s)
| | | | | | - Jie Huang
- Department of Genetics and Biostatistics, University of North Carolina Chapel Hill, Chapel Hill, NC, USA and
| | - Yun Li
- Department of Genetics and Biostatistics, University of North Carolina Chapel Hill, Chapel Hill, NC, USA and
| | | | | | | | - Jiangping Wu
- Centre de Recherche and Service de Néphrologie, Centre Hospitalier de L'Université de Montréal (CRCHUM), Montréal, QC, Canada,
| |
Collapse
|
27
|
Glorieux C, Auquier J, Dejeans N, Sid B, Demoulin JB, Bertrand L, Verrax J, Calderon PB. Catalase expression in MCF-7 breast cancer cells is mainly controlled by PI3K/Akt/mTor signaling pathway. Biochem Pharmacol 2014; 89:217-23. [PMID: 24630930 DOI: 10.1016/j.bcp.2014.02.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 02/25/2014] [Accepted: 02/26/2014] [Indexed: 01/21/2023]
Abstract
Catalase is an antioxidant enzyme that catalyzes mainly the transformation of hydrogen peroxide into water and oxygen. Although catalase is frequently down-regulated in tumors the underlying mechanism remains unclear. Few transcription factors have been reported to directly bind the human catalase promoter. Among them FoxO3a has been proposed as a positive regulator of catalase expression. Therefore, we decided to study the role of the transcription factor FoxO3a and the phosphatidylinositol-3 kinase (PI3K) signaling pathway, which regulates FoxO3a, in the expression of catalase. To this end, we developed an experimental model of mammary breast MCF-7 cancer cells that acquire resistance to oxidative stress, the so-called Resox cells, in which catalase is overexpressed as compared with MCF-7 parental cell line. In Resox cells, Akt expression is decreased but its phosphorylation is enhanced when compared with MCF-7 cells. A similar profile is observed for FoxO3a, with less total protein but more phosphorylated FoxO3a in Resox cells, correlating with its higher Akt activity. The modulation of FoxO3a expression by knockdown and overexpression strategies did not affect catalase expression, neither in MCF-7 nor in Resox cells. Inhibition of PI3K and mTOR by LY295002 and rapamycin, respectively, decreases the phosphorylation of downstream targets (i.e. GSK3β and p70S6K) and leads to an increase of catalase expression only in MCF-7 but not in Resox cells. In conclusion, FoxO3a does not appear to play a critical role in the regulation of catalase expression in both cancer cells. Only MCF-7 cells are sensitive and dependent on PI3K/Akt/mTOR signaling.
Collapse
Affiliation(s)
- Christophe Glorieux
- Université catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group, Brussels, Belgium
| | - Julien Auquier
- Université catholique de Louvain, Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Brussels, Belgium
| | | | - Brice Sid
- Université catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group, Brussels, Belgium
| | - Jean-Baptiste Demoulin
- Université catholique de Louvain, de Duve Institute, Experimental Medicine Unit, Brussels, Belgium
| | - Luc Bertrand
- Université catholique de Louvain, Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Brussels, Belgium
| | - Julien Verrax
- Université catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group, Brussels, Belgium
| | - Pedro Buc Calderon
- Université catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group, Brussels, Belgium; Facultad de Ciencias de la Salud, Universidad Arturo Prat, Iquique, Chile.
| |
Collapse
|
28
|
LIU XIAOLIANG, QI FANG, WU WEI. Effect of intervention in the diacylglycerol-protein kinase C signaling pathway on JNK1 expression and its downstream signaling in diabetic cardiomyopathy. Mol Med Rep 2014; 9:979-84. [DOI: 10.3892/mmr.2014.1904] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 12/10/2013] [Indexed: 11/05/2022] Open
|
29
|
Bruhn MA, Pearson RB, Hannan RD, Sheppard KE. AKT-independent PI3-K signaling in cancer - emerging role for SGK3. Cancer Manag Res 2013; 5:281-92. [PMID: 24009430 PMCID: PMC3762672 DOI: 10.2147/cmar.s35178] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The phosphoinositide 3-kinase (PI3-K) signaling pathway plays an important role in a wide variety of fundamental cellular processes, largely mediated via protein kinase B/v-akt murine thymoma viral oncogene homolog (PKB/AKT) signaling. Given the crucial role of PI3-K/AKT signaling in regulating processes such as cell growth, proliferation, and survival, it is not surprising that components of this pathway are frequently dysregulated in cancer, making the AKT kinase family members important therapeutic targets. The large number of clinical trials currently evaluating PI3-K pathway inhibitors as a therapeutic strategy further emphasizes this. The serum- and glucocorticoid-inducible protein kinase (SGK) family is made up of three isoforms, SGK1, 2, and 3, that are PI3-K-dependent, serine/threonine kinases, with similar substrate specificity to AKT. Consequently, the SGK family also regulates similar cell processes to the AKT kinases, including cell proliferation and survival. Importantly, there is emerging evidence demonstrating that SGK3 plays a critical role in AKT-independent oncogenic signaling. This review will focus on the role of SGK3 as a key effector of AKT-independent PI3-K oncogenic signaling.
Collapse
Affiliation(s)
- Maressa A Bruhn
- Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia ; School of Biological Sciences, Flinders University, Bedford Park, South Australia, Australia
| | | | | | | |
Collapse
|
30
|
Lollo P, Batista T, Moura C, Morato P, Cruz A, Faria J, Carneiro E, Amaya-Farfan J. l-Leucine supplemented whey protein. Dose–response effect on heart mTOR activation of sedentary and trained rats. Food Res Int 2013. [DOI: 10.1016/j.foodres.2013.05.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
31
|
Demeulder B, Zarrinpashneh E, Ginion A, Viollet B, Hue L, Rider MH, Vanoverschelde JL, Beauloye C, Horman S, Bertrand L. Differential regulation of eEF2 and p70S6K by AMPKalpha2 in heart. Biochim Biophys Acta Mol Basis Dis 2013; 1832:780-90. [DOI: 10.1016/j.bbadis.2013.02.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 02/17/2013] [Accepted: 02/25/2013] [Indexed: 01/13/2023]
|
32
|
Gray S, Da Boit M. Marine n-3 polyunsaturated fatty acids: a potential role in the treatment of sarcopenia. ACTA ACUST UNITED AC 2013. [DOI: 10.2217/clp.13.10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
33
|
Witham WG, Yester KA, McGaffin KR. A high leucine diet mitigates cardiac injury and improves survival after acute myocardial infarction. Metabolism 2013; 62:290-302. [PMID: 22935555 DOI: 10.1016/j.metabol.2012.07.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 07/17/2012] [Accepted: 07/27/2012] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Evidence suggests that branched chain amino acids (BCAAs) are beneficial in treating human disease. It is unknown, however, what impact BCAAs have on outcomes in acute myocardial infarction (MI). This study was performed to test the hypothesis that the specific BCAA leucine mitigates cardiac injury and improves survival post-MI. MATERIALS/METHODS 11-12 week old male C57BL/6 mice were subjected to experimental MI or sham procedure, and provided regular chow (RC; 1.5% leucine) or a high leucine diet (HLD; 5% leucine), and followed for 3½ or 28 days. All mice were studied by echocardiography and cardiac catheterization, and all hearts were collected for histologic measurements of hypertrophy, fibrosis and apoptosis. Inflammation, hypertrophic gene expression, signal transduction, and glucose, palmitate and leucine metabolism were also measured in 3½day hearts. RESULTS Except for increased leucine and decreased glucose oxidation, an HLD had no effect on measured outcomes in sham mice. With MI, cardiac structure, function, and survival were significantly improved with an HLD. At 3½days post-MI, an HLD increased cardiac hypertrophic signaling and decreased inflammation. Cardiac leucine oxidation was decreased in RC mice post-MI, but significantly increased with an HLD. These changes in metabolism were accompanied by a significant increase in cardiac ATP content in the HLD group. Finally, at both 3½ and 28 days post-MI, an HLD increased compensatory hypertrophy, and attenuated cardiac fibrosis and apoptosis. CONCLUSIONS An HLD increases compensatory hypertrophy, attenuates fibrosis and apoptosis, and positively modulates oxidative metabolism to improve cardiac structure, function, and survival post-MI.
Collapse
Affiliation(s)
- William G Witham
- Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
| | | | | |
Collapse
|
34
|
Wiza C, Nascimento EBM, Ouwens DM. Role of PRAS40 in Akt and mTOR signaling in health and disease. Am J Physiol Endocrinol Metab 2012; 302:E1453-60. [PMID: 22354785 DOI: 10.1152/ajpendo.00660.2011] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The proline-rich Akt substrate of 40 kDa (PRAS40) acts at the intersection of the Akt- and mammalian target of rapamycin (mTOR)-mediated signaling pathways. The protein kinase mTOR is the catalytic subunit of two distinct signaling complexes, mTOR complex 1 (mTORC1) and mTORC2, that link energy and nutrients to the regulation of cellular growth and energy metabolism. Activation of mTOR in response to nutrients and growth factors results in the phosphorylation of numerous substrates, including the phosphorylations of S6 kinase by mTORC1 and Akt by mTORC2. Alterations in Akt and mTOR activity have been linked to the progression of multiple diseases such as cancer and type 2 diabetes. Although PRAS40 was first reported as substrate for Akt, investigations toward mTOR-binding partners subsequently identified PRAS40 as both component and substrate of mTORC1. Phosphorylation of PRAS40 by Akt and by mTORC1 itself results in dissociation of PRAS40 from mTORC1 and may relieve an inhibitory constraint on mTORC1 activity. Adding to the complexity is that gene silencing studies indicate that PRAS40 is also necessary for the activity of the mTORC1 complex. This review summarizes the regulation and potential function(s) of PRAS40 in the complex Akt- and mTOR-signaling network in health and disease.
Collapse
Affiliation(s)
- Claudia Wiza
- Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Düsseldorf, Germany
| | | | | |
Collapse
|
35
|
Kamolrat T, Gray SR, Thivierge MC. Fish oil positively regulates anabolic signalling alongside an increase in whole-body gluconeogenesis in ageing skeletal muscle. Eur J Nutr 2012; 52:647-57. [PMID: 22581256 DOI: 10.1007/s00394-012-0368-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 04/24/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE Fish oil, containing mainly long-chain n-3 polyunsaturated fatty acids (LCn-3PUFA), has been found to acutely stimulate protein synthesis and insulin-mediated glucose metabolism. However, the underlying mechanism and more prolonged effect of fish oil during ageing remain to be determined. METHODS Fish oil (EPAX6000; 49.6 % eicosapentaenoic acid, 50.4 % docosahexaenoic acid) or control oil (60 % olive, 40 % soy) supplementation was delivered, via chocolate-derived sweets, to rats for 8 weeks. Throughout the study, food intake and body weight were recorded and body composition was investigated using EchoMRI. During the last 40 min of a 6 h infusion, with labelled dextrose ([U-(13)C]glucose) and amino acids ([1-(13)C]phenylalanine), blood samples were collected to assess glucose and phenylalanine kinetics. Soleus and longissimus dorsi muscles were extracted for protein and mRNA analyses. RESULTS Fish oil had no effect on food intake or body composition. An increased whole-body glucose turnover, mainly accounted for via an increase in endogenous glucose production, was observed with fish oil feeding. No effects on whole-body phenylalanine turnover were observed. In longissimus dorsi, fish oil augmented the phosphorylation of phosphoinositide 3-kinase (PI3K)([Tyr458]) (P = 0.04) and 70 kDa ribosomal protein S6 kinase (p70s6k)([Thr389]) (P = 0.04). There were no differences in protein kinase B (Akt)([Ser473]), mammalian target of rapamycin (mTOR)([Ser2448]), protein phosphatase 2A (PP2A) 56 kDa regulatory B subunit γ (PP2A-B56-γ), forkhead box containing proteins O-subclass 3a (FOX03a)([Ser253]) or inflammatory markers (Interleukin-6, Interleukin-1 β, tumour necrosis factor-α, and cyclooxygenase-2). CONCLUSIONS Our data suggest that the fish oil may stimulate endogenous glucose production and increase anabolic signalling in ageing rats.
Collapse
Affiliation(s)
- Torkamol Kamolrat
- Musculoskeletal Research Programme, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, UK
| | | | | |
Collapse
|
36
|
Kalista S, Schakman O, Gilson H, Lause P, Demeulder B, Bertrand L, Pende M, Thissen JP. The type 1 insulin-like growth factor receptor (IGF-IR) pathway is mandatory for the follistatin-induced skeletal muscle hypertrophy. Endocrinology 2012; 153:241-53. [PMID: 22087027 DOI: 10.1210/en.2011-1687] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Myostatin inhibition by follistatin (FS) offers a new approach for muscle mass enhancement. The aim of the present study was to characterize the mediators responsible for the FS hypertrophic action on skeletal muscle in male mice. Because IGF-I and IGF-II, two crucial skeletal muscle growth factors, are induced by myostatin inhibition, we assessed their role in FS action. First, we tested whether type 1 IGF receptor (IGF-IR) is required for FS-induced hypertrophy. By using mice expressing a dominant-negative IGF-IR in skeletal muscle, we showed that IGF-IR inhibition blunted by 63% fiber hypertrophy caused by FS. Second, we showed that FS caused the same degree of fiber hypertrophy in wild-type and IGF-II knockout mice. We then tested the role of the signaling molecules stimulated by IGF-IR, in particular the Akt/mammalian target of rapamycin (mTOR)/70-kDa ribosomal protein S6 kinase (S6K) pathway. We investigated whether Akt phosphorylation is required for the FS action. By cotransfecting a dominant-negative form of Akt together with FS, we showed that Akt inhibition reduced by 65% fiber hypertrophy caused by FS. Second, we evaluated the role of mTOR in FS action. Fiber hypertrophy induced by FS was reduced by 36% in rapamycin-treated mice. Finally, because the activity of S6K is increased by FS, we tested its role in FS action. FS caused the same degree of fiber hypertrophy in wild-type and S6K1/2 knockout mice. In conclusion, the IGF-IR/Akt/mTOR pathway plays a critical role in FS-induced muscle hypertrophy. In contrast, induction of IGF-II expression and S6K activity by FS are not required for the hypertrophic action of FS.
Collapse
Affiliation(s)
- S Kalista
- Pole of Endocrinology, Diabetes, and Nutrition, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Avenue Hippocrate 55 bte B1.55.06, B-1200 Brussels, Belgium.
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Aranda-Orgillés B, Rutschow D, Zeller R, Karagiannidis AI, Köhler A, Chen C, Wilson T, Krause S, Roepcke S, Lilley D, Schneider R, Schweiger S. Protein phosphatase 2A (PP2A)-specific ubiquitin ligase MID1 is a sequence-dependent regulator of translation efficiency controlling 3-phosphoinositide-dependent protein kinase-1 (PDPK-1). J Biol Chem 2011; 286:39945-57. [PMID: 21930711 PMCID: PMC3220588 DOI: 10.1074/jbc.m111.224451] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 09/09/2011] [Indexed: 02/02/2023] Open
Abstract
We have shown previously that the ubiquitin ligase MID1, mutations of which cause the midline malformation Opitz BBB/G syndrome (OS), serves as scaffold for a microtubule-associated protein complex that regulates protein phosphatase 2A (PP2A) activity in a ubiquitin-dependent manner. Here, we show that the MID1 protein complex associates with mRNAs via a purine-rich sequence motif called MIDAS (MID1 association sequence) and thereby increases stability and translational efficiency of these mRNAs. Strikingly, inclusion of multiple copies of the MIDAS motif into mammalian mRNAs increases production of the encoded proteins up to 20-fold. Mutated MID1, as found in OS patients, loses its influence on MIDAS-containing mRNAs, suggesting that the malformations in OS patients could be caused by failures in the regulation of cytoskeleton-bound protein translation. This is supported by the observation that the majority of mRNAs that carry MIDAS motifs is involved in developmental processes and/or energy homeostasis. Further analysis of one of the proteins encoded by a MIDAS-containing mRNA, namely PDPK-1 (3-phosphoinositide dependent protein kinase-1), which is an important regulator of mammalian target of rapamycin/PP2A signaling, showed that PDPK-1 protein synthesis is significantly reduced in cells from an OS patient compared with an age-matched control and can be rescued by functional MID1. Together, our data uncover a novel messenger ribonucleoprotein complex that regulates microtubule-associated protein translation. They suggest a novel mechanism underlying OS and point at an enormous potential of the MIDAS motif to increase the efficiency of biotechnological protein production in mammalian cells.
Collapse
Affiliation(s)
| | - Désirée Rutschow
- the Division of Medical Sciences, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, Scotland, United Kingdom
| | - Raphael Zeller
- the Division of Medical Sciences, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, Scotland, United Kingdom
| | - Antonios I. Karagiannidis
- the Institute of Biochemistry, Center of Molecular Biosciences Innsbruck, University of Innsbruck, 6020 Innsbruck, Austria
| | - Andrea Köhler
- the Institute of Biochemistry, Center of Molecular Biosciences Innsbruck, University of Innsbruck, 6020 Innsbruck, Austria
| | - Changwei Chen
- the Division of Medical Sciences, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, Scotland, United Kingdom
| | - Timothy Wilson
- the College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom, and
| | - Sven Krause
- From the Max-Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
| | - Stefan Roepcke
- From the Max-Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
| | - David Lilley
- the College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom, and
| | - Rainer Schneider
- From the Max-Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
- the Institute of Biochemistry, Center of Molecular Biosciences Innsbruck, University of Innsbruck, 6020 Innsbruck, Austria
| | - Susann Schweiger
- From the Max-Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
- the Division of Medical Sciences, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, Scotland, United Kingdom
| |
Collapse
|
38
|
Kwak SS, Suk J, Choi JH, Yang S, Kim JW, Sohn S, Chung JH, Hong YH, Lee DH, Ahn JK, Min H, Fu YM, Meadows GG, Joe CO. Autophagy induction by tetrahydrobiopterin deficiency. Autophagy 2011; 7:1323-34. [PMID: 21795851 PMCID: PMC3242797 DOI: 10.4161/auto.7.11.16627] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 07/13/2011] [Accepted: 07/13/2011] [Indexed: 01/13/2023] Open
Abstract
Tetrahydrobiopterin (BH₄) deficiency is a genetic disorder associated with a variety of metabolic syndromes such as phenylketonuria (PKU). In this article, the signaling pathway by which BH₄ deficiency inactivates mTORC1 leading to the activation of the autophagic pathway was studied utilizing BH₄-deficient Spr(-/-) mice generated by the knockout of the gene encoding sepiapterin reductase (SR) catalyzing BH₄ synthesis. We found that mTORC1 signaling was inactivated and autophagic pathway was activated in tissues from Spr(-/-) mice. This study demonstrates that tyrosine deficiency causes mTORC1 inactivation and subsequent activation of autophagic pathway in Spr(-/-) mice. Therapeutic tyrosine diet completely rescued dwarfism and mTORC1 inhibition but inactivated autophagic pathway in Spr(-/-) mice. Tyrosine-dependent inactivation of mTORC1 was further supported by mTORC1 inactivation in Pah(enu2) mouse model lacking phenylalanine hydroxylase (Pah). NIH3T3 cells grown under the condition of tyrosine restriction exhibited autophagy induction. However, mTORC1 activation by RhebQ64L, a positive regulator of mTORC1, inactivated autophagic pathway in NIH3T3 cells under tyrosine-deficient conditions. In addition, this study first documents mTORC1 inactivation and autophagy induction in PKU patients with BH₄ deficiency.
Collapse
Affiliation(s)
- Sang Su Kwak
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Higuchi N, Kato M, Miyazaki M, Tanaka M, Kohjima M, Ito T, Nakamuta M, Enjoji M, Kotoh K, Takayanagi R. Potential role of branched-chain amino acids in glucose metabolism through the accelerated induction of the glucose-sensing apparatus in the liver. J Cell Biochem 2011; 112:30-8. [PMID: 20506195 DOI: 10.1002/jcb.22688] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Branched-chain amino acids (BCAAs) have a potential to improve glucose metabolism in cirrhotic patients; however, the contribution of liver in this process has not been clarified. To estimate the effect of BCAA on glucose metabolism in liver, we evaluated the mRNA expression levels of glucose-sensing apparatus genes in HepG2 cells and in rat liver after oral administration of BCAA. HepG2 cells were cultured in low glucose (100 mg/dl) or high glucose (400 mg/dl) in the absence or presence of BCAA. The mRNA expression levels and protein levels of GLUT2 and liver-type glucokinase (L-GK) were estimated using RT-PCR and immunoblotting. The expression levels of transcriptional factors, including SREBP-1c, ChREBP, PPAR-γm and LXRα, were estimated. The mRNA expression levels of transcriptional factors, glycogen synthase, and genes involved in gluconeogenesis were evaluated in rat liver at 3 h after the administration of BCAA. BCAA accelerated the expression of GLUT2 and L-GK in HepG2 cells in high glucose. Expression levels of ChREBP, SREBP-1c, and LXRα were also increased in this condition. BCAA administration enhanced the mRNA expression levels of L-GK, SREBP-1c, and LXRα and suppressed the expression levels of G-6-Pase in rat liver, without affecting the expression levels of glycogen synthase or serum glucose concentrations. BCAA administration enhanced the bioactivity of the glucose-sensing apparatus, probably via the activation of a transcriptional mechanism, suggesting that these amino acids may improve glucose metabolism through the accelerated utility of glucose and glucose-6-phosphate in the liver.
Collapse
Affiliation(s)
- Nobito Higuchi
- Department of Medicine and Bioregulatory Science, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Deldicque L, Bertrand L, Patton A, Francaux M, Baar K. ER stress induces anabolic resistance in muscle cells through PKB-induced blockade of mTORC1. PLoS One 2011; 6:e20993. [PMID: 21698202 PMCID: PMC3116857 DOI: 10.1371/journal.pone.0020993] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Accepted: 05/17/2011] [Indexed: 12/31/2022] Open
Abstract
Background Anabolic resistance is the inability to increase protein synthesis in response to an increase in amino acids following a meal. One potential mediator of anabolic resistance is endoplasmic reticulum (ER) stress. The purpose of the present study was to test whether ER stress impairs the response to growth factors and leucine in muscle cells. Methods Muscle cells were incubated overnight with tunicamycin or thapsigargin to induce ER stress and the activation of the unfolded protein response, mTORC1 activity at baseline and following insulin and amino acids, as well as amino acid transport were determined. Results ER stress decreased basal phosphorylation of PKB and S6K1 in a dose-dependent manner. In spite of the decrease in basal PKB phosphorylation, insulin (10–50 nM) could still activate both PKB and S6K1. The leucine (2.5–5 mM)-induced phosphorylation of S6K1 on the other hand was repressed by low concentrations of both tunicamycin and thapsigargin. To determine the mechanism underlying this anabolic resistance, several inhibitors of mTORC1 activation were measured. Tunicamycin and thapsigargin did not change the phosphorylation or content of either AMPK or JNK, both increased TRB3 mRNA expression and thapsigargin increased REDD1 mRNA. Tunicamycin and thapsigargin both decreased the basal phosphorylation state of PRAS40. Neither tunicamycin nor thapsigargin prevented phosphorylation of PRAS40 by insulin. However, since PKB is not activated by amino acids, PRAS40 phosphorylation remained low following the addition of leucine. Blocking PKB using a specific inhibitor had the same effect on both PRAS40 and leucine-induced phosphorylation of S6K1. Conclusion ER stress induces anabolic resistance in muscle cells through a PKB/PRAS40-induced blockade of mTORC1.
Collapse
Affiliation(s)
- Louise Deldicque
- Université catholique de Louvain, Institute of Neuroscience, Research Group in Muscle and Exercise Physiology, Louvain-la-Neuve, Belgium
- Research Centre for Exercise and Health, Department of Biomedical Kinesiology, K.U. Leuven, Leuven, Belgium
| | - Luc Bertrand
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Woluwe-Saint-Lambert, Belgium
| | - Amy Patton
- Department of Neurobiology, Physiology and Behaviour, University of California Davis, Davis, California, United States of America
| | - Marc Francaux
- Université catholique de Louvain, Institute of Neuroscience, Research Group in Muscle and Exercise Physiology, Louvain-la-Neuve, Belgium
| | - Keith Baar
- Department of Neurobiology, Physiology and Behaviour, University of California Davis, Davis, California, United States of America
- * E-mail:
| |
Collapse
|
41
|
Sepsis-induced alterations in protein-protein interactions within mTOR complex 1 and the modulating effect of leucine on muscle protein synthesis. Shock 2011; 35:117-25. [PMID: 20577146 DOI: 10.1097/shk.0b013e3181ecb57c] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Sepsis-induced muscle atrophy is produced in part by decreased protein synthesis mediated by inhibition of mTOR (mammalian target of rapamycin). The present study tests the hypothesis that alteration of specific protein-protein interactions within the mTORC1 (mTOR complex 1) contributes to the decreased mTOR activity observed after cecal ligation and puncture in rats. Sepsis decreased in vivo translational efficiency in gastrocnemius and reduced the phosphorylation of eukaryotic initiation factor (eIF) 4E-binding protein (BP) 1, S6 kinase (S6K) 1, and mTOR, compared with time-matched pair-fed controls. Sepsis decreased T246-phosphorylated PRAS40 (proline-rich Akt substrate 40) and reciprocally increased S792-phosphorylated raptor (regulatory associated protein of mTOR). Despite these phosphorylation changes, sepsis did not alter PRAS40 binding to raptor. The amount of the mTOR-raptor complex did not differ between groups. In contrast, the binding and retention of both 4E-BP1 and S6K1 to raptor were increased, and, conversely, the binding of raptor with eIF3 was decreased in sepsis. These changes in mTORC1 in the basal state were associated with enhanced 5'-AMP activated kinase activity. Acute in vivo leucine stimulation increased muscle protein synthesis in control, but not septic rats. This muscle leucine resistance was associated with coordinated changes in raptor-eIF3 binding and 4E-BP1 phosphorylation. Overall, our data suggest the sepsis-induced decrease in muscle protein synthesis may be mediated by the inability of 4E-BP1 and S6K1 to be phosphorylated and released from mTORC1 as well as the decreased recruitment of eIF3 necessary for a functional 48S complex. These data provide additional mechanistic insight into the molecular mechanisms by which sepsis impairs both basal protein synthesis and the anabolic response to the nutrient signal leucine in skeletal muscle.
Collapse
|
42
|
Brown LD, Green AS, Limesand SW, Rozance PJ. Maternal amino acid supplementation for intrauterine growth restriction. Front Biosci (Schol Ed) 2011; 3:428-44. [PMID: 21196387 DOI: 10.2741/s162] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Maternal dietary protein supplementation to improve fetal growth has been considered as an option to prevent or treat intrauterine growth restriction. However, in contrast to balanced dietary supplementation, adverse perinatal outcomes in pregnant women who received high amounts of dietary protein supplementation have been observed. The responsible mechanisms for these adverse outcomes are unknown. This review will discuss relevant human and animal data to provide the background necessary for the development of explanatory hypotheses and ultimately for the development therapeutic interventions during pregnancy to improve fetal growth. Relevant aspects of fetal amino acid metabolism during normal pregnancy and those pregnancies affected by IUGR will be discussed. In addition, data from animal experiments which have attempted to determine mechanisms to explain the adverse responses identified in the human trials will be presented. Finally, we will suggest new avenues for investigation into how amino acid supplementation might be used safely to treat and/or prevent IUGR.
Collapse
Affiliation(s)
- Laura D Brown
- Department of Pediatrics, University of Colorado Denver; Aurora, CO 80045, USA
| | | | | | | |
Collapse
|
43
|
Suryawan A, Davis TA. The abundance and activation of mTORC1 regulators in skeletal muscle of neonatal pigs are modulated by insulin, amino acids, and age. J Appl Physiol (1985) 2010; 109:1448-54. [PMID: 20724570 DOI: 10.1152/japplphysiol.00428.2010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mammalian target of rapamycin complex 1 (mTORC1) signaling is crucial for the regulation of protein synthesis. Most of known mTORC1 regulators have been isolated and characterized using cell culture systems, and the physiological roles of these regulators have not been fully tested in vivo. Previously we demonstrated that the insulin (INS) and amino acid (AA)-induced activation of mTORC1 is developmentally regulated in skeletal muscle (Suryawan A et al. Am J Physiol Endocrinol Metab 293: E1597-E1605, 2007). The present study aimed to characterize in more detail the effects of the postprandial rise in INS and AA on the activation and abundance of mTORC1 regulators in muscle and how this is modified by development. Overnight fasted 6- and 26-day-old pigs were studied during 1) euinsulinemic-euglycemic-euaminoacidemic conditions (control), 2) euinsulinemic-euglycemic-hyperaminoacidemic clamps (AA), and 3) hyperinsulinemic-euglycemic-euaminoacidemic clamps (INS). INS, but not AA, enhanced the PRAS40 phosphorylation, and this effect was greater in 6- than in 26-day old pigs. Phospholipase D1 (PLD1) abundance and phosphorylation, and the association of PLD1 with Ras homolog enriched in brain (Rheb), were greater in the younger pigs. Neither INS, AA, nor age altered the abundance of Rheb, vacuolar protein sorting 34 (Vps34), or FK506-binding protein 38 (FKBP38). Although INS and AA had no effect, the abundance of ras-related GTP binding B (RagB) and the association of RagB with Raptor were greater in 6- than in 26-day-old pigs. Neither INS, AA, nor age altered AMPK-induced phosphorylation of Raptor. Our results suggest that the enhanced activation of mTORC1 in muscle of neonatal pigs is in part due to regulation by PRAS40, PLD1, and the Rag GTPases.
Collapse
Affiliation(s)
- Agus Suryawan
- United States Department of Agriculture/Agriculture Research Service Children's Nutrition Research Center, Department of Paediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | | |
Collapse
|
44
|
Lang CH, Lynch CJ, Vary TC. BCATm deficiency ameliorates endotoxin-induced decrease in muscle protein synthesis and improves survival in septic mice. Am J Physiol Regul Integr Comp Physiol 2010; 299:R935-44. [PMID: 20554928 DOI: 10.1152/ajpregu.00297.2010] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Endotoxin (LPS) and sepsis decrease mammalian target of rapamycin (mTOR) activity in skeletal muscle, thereby reducing protein synthesis. Our study tests the hypothesis that inhibition of branched-chain amino acid (BCAA) catabolism, which elevates circulating BCAA and stimulates mTOR, will blunt the LPS-induced decrease in muscle protein synthesis. Wild-type (WT) and mitochondrial branched-chain aminotransferase (BCATm) knockout mice were studied 4 h after Escherichia coli LPS or saline. Basal skeletal muscle protein synthesis was increased in knockout mice compared with WT, and this change was associated with increased eukaryotic initiation factor (eIF)-4E binding protein-1 (4E-BP1) phosphorylation, eIF4E.eIF4G binding, 4E-BP1.raptor binding, and eIF3.raptor binding without a change in the mTOR.raptor complex in muscle. LPS decreased muscle protein synthesis in WT mice, a change associated with decreased 4E-BP1 phosphorylation as well as decreased formation of eIF4E.eIF4G, 4E-BP1.raptor, and eIF3.raptor complexes. In BCATm knockout mice given LPS, muscle protein synthesis only decreased to values found in vehicle-treated WT control mice, and this ameliorated LPS effect was associated with a coordinate increase in 4E-BP1.raptor, eIF3.raptor, and 4E-BP1 phosphorylation. Additionally, the LPS-induced increase in muscle cytokines was blunted in BCATm knockout mice, compared with WT animals. In a separate study, 7-day survival and muscle mass were increased in BCATm knockout vs. WT mice after polymicrobial peritonitis. These data suggest that elevating blood BCAA is sufficient to ameliorate the catabolic effect of LPS on skeletal muscle protein synthesis via alterations in protein-protein interactions within mTOR complex-1, and this may provide a survival advantage in response to bacterial infection.
Collapse
Affiliation(s)
- Charles H Lang
- Department of Cellular and Molecular Physiology, and Surgery, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA.
| | | | | |
Collapse
|
45
|
Thomson DM, Hancock CR, Evanson BG, Kenney SG, Malan BB, Mongillo AD, Brown JD, Hepworth S, Fillmore N, Parcell AC, Kooyman DL, Winder WW. Skeletal muscle dysfunction in muscle-specific LKB1 knockout mice. J Appl Physiol (1985) 2010; 108:1775-85. [PMID: 20360428 DOI: 10.1152/japplphysiol.01293.2009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Liver kinase B1 (LKB1) is a tumor-suppressing protein that is involved in the regulation of muscle metabolism and growth by phosphorylating and activating AMP-activated protein kinase (AMPK) family members. Here we report the development of a myopathic phenotype in skeletal and cardiac muscle-specific LKB1 knockout (mLKB1-KO) mice. The myopathic phenotype becomes overtly apparent at 30-50 wk of age and is characterized by decreased body weight and a proportional reduction in fast-twitch skeletal muscle weight. The ability to ambulate is compromised with an often complete loss of hindlimb function. Skeletal muscle atrophy is associated with a 50-75% reduction in mammalian target of rapamycin pathway phosphorylation, as well as lower peroxisome proliferator-activated receptor-alpha coactivator-1 content and cAMP response element binding protein phosphorylation (43 and 40% lower in mLKB1-KO mice, respectively). Maximum in situ specific force production is not affected, but fatigue is exaggerated, and relaxation kinetics are slowed in the myopathic mice. The increased fatigue is associated with a 30-78% decrease in mitochondrial protein content, a shift away from type IIA/D toward type IIB muscle fibers, and a tendency (P=0.07) for decreased capillarity in mLKB1-KO muscles. Hearts from myopathic mLKB1-KO mice exhibit grossly dilated atria, suggesting cardiac insufficiency and heart failure, which likely contributes to the phenotype. These findings indicate that LKB1 plays a critical role in the maintenance of both skeletal and cardiac function.
Collapse
Affiliation(s)
- David M Thomson
- Department of Physiology and Developmental Biology, 589 WIDB, Brigham Young University, Provo, UT 84602, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|