1
|
Yao H, Li K, Wei J, Lin Y, Liu Y. The contradictory role of branched-chain amino acids in lifespan and insulin resistance. Front Nutr 2023; 10:1189982. [PMID: 37408986 PMCID: PMC10318341 DOI: 10.3389/fnut.2023.1189982] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/26/2023] [Indexed: 07/07/2023] Open
Abstract
Branched-chain amino acids (BCAAs; a mixture of leucine, valine and isoleucine) have important regulatory effects on glucose and lipid metabolism, protein synthesis and longevity. Many studies have reported that circulating BCAA levels or dietary intake of BCAAs is associated with longevity, sarcopenia, obesity, and diabetes. Among them, the influence of BCAAs on aging and insulin resistance often present different benefits or harmful effects in the elderly and in animals. Considering the nonobvious correlation between circulating BCAA levels and BCAA uptake, as well as the influence of diseases, diet and aging on the body, some of the contradictory conclusions have been drawn. The regulatory mechanism of the remaining contradictory role may be related to endogenous branched-chain amino acid levels, branched-chain amino acid metabolism and mTOR-related autophagy. Furthermore, the recent discovery that insulin resistance may be independent of longevity has expanded the research thinking related to the regulatory mechanism among the three. However, the negative effects of BCAAs on longevity and insulin resistance were mostly observed in high-fat diet-fed subjects or obese individuals, while the effects in other diseases still need to be studied further. In conclusion, there is still no definite conclusion on the specific conditions under which BCAAs and insulin resistance extend life, shorten life, or do not change lifespan, and there is still no credible and comprehensive explanation for the different effects of BCAAs and insulin resistance on lifespan.
Collapse
Affiliation(s)
- He Yao
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Kai Li
- Department of General Surgery, The First People’s Hospital of Taian, Taian, Shandong, China
| | - Jie Wei
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Yajun Lin
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Yinghua Liu
- Department of Nutrition, National Clinical Research Center for Geriatric Diseases, The First Medical Center of Chinese PLA General Hospital, Beijing, China
| |
Collapse
|
2
|
Zhou L, Feng W, Mao Y, Chen Y, Zhang X. Nanoengineered sonosensitive platelets for synergistically augmented sonodynamic tumor therapy by glutamine deprivation and cascading thrombosis. Bioact Mater 2022; 24:26-36. [PMID: 36582345 PMCID: PMC9761609 DOI: 10.1016/j.bioactmat.2022.11.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/06/2022] [Accepted: 11/27/2022] [Indexed: 12/14/2022] Open
Abstract
Ultrasound (US)-activated sonodynamic therapy (SDT) stands for a distinct antitumor modality because of its attractive characteristics including intriguing noninvasiveness, desirable safety, and high tissue penetration depth, which, unfortunately, suffers from compromised therapeutic efficacy due to cancer cell-inherent adaptive mechanisms, such as glutathione (GSH) neutralization response to reactive oxygen species (ROS), and glutamine addictive properties of tumors. In this work, we developed a biological sonosensitive platelet (PLT) pharmacytes for favoring US/GSH-responsive combinational therapeutic of glutamine deprivation and augmented SDT. The amino acid transporter SLC6A14 blockade agent α-methyl-DL-tryptophan (α-MT)-loaded and MnO2-coated porphyrinic metal-organic framework (MOF) nanoparticles were encapsulated in the PLTs through the physical adsorption of electrostatic attraction and the intrinsic endocytosis of PLTs. When the sonosensitive PLT pharmacytes reached tumor sites through their natural tendencies to TME, US stimulated the PLTs-loaded porphyrinic MOF to generate ROS, resulting in morphological changes of the PLTs and the release of nanoparticles. Subsequently, intracellular high concentration of GSH and extracellular spatio-temporal controlled US irradiation programmatically triggered the release of α-MT, which enabled the synergistically amplified SDT by inducing amino acid starvation, inhibiting mTOR, and mediating ferroptosis. In addition, US stimulation achieved the targeted activation of PLTs at tumor vascular site, which evolved from circulating PLTs to dendritic PLTs, effectively blocking the blood supply of tumors through thrombus formation, and revealing the encouraging potential to facilitate tumor therapeutics.
Collapse
Affiliation(s)
- Liqiang Zhou
- MOE Frontiers Science Center for Precision Oncology, Faculty of Health Sciences, University of Macau, Macau, SAR, 999078, China
| | - Wei Feng
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, China
| | - Yuhang Mao
- School of Medical Technology, Xi'an Medical College, Xi'an, 710021, Shanxi, China
| | - Yu Chen
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, China,Corresponding author.
| | - Xuanjun Zhang
- MOE Frontiers Science Center for Precision Oncology, Faculty of Health Sciences, University of Macau, Macau, SAR, 999078, China,Corresponding author.
| |
Collapse
|
3
|
Han G, Kim J, Kim JM, Kil D. Transcriptomic analysis of the liver in aged laying hens with different eggshell strength. Poult Sci 2022; 102:102217. [PMID: 36343436 PMCID: PMC9646969 DOI: 10.1016/j.psj.2022.102217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/06/2022] [Accepted: 09/29/2022] [Indexed: 11/06/2022] Open
Abstract
Eggshell is composed of a very ordered and mineralized structure and is important for egg quality. Eggshell strength is particularly important because of its direct association with economic outcomes and egg safety. Various factors related to laying hens and their environment affects eggshell strength. However, the molecular mechanisms of liver functions related to decreased eggshell strength of aged laying hens are largely unknown. Therefore, this study aimed to identify potential factors affecting eggshell strength in aged laying hens at the hepatic transcriptomic level. A total of five hundred 92-wk-old Hy-line Brown laying hens were screened to select those exhibiting the greatest variation in eggshell strength. Based on the final eggshell strength, 12 hens producing eggs with strong eggshell strength (SES) and weak eggshell strength (WES) were finally selected (n = 6) for liver tissue sampling. The RNA-sequencing was performed to identify differentially expressed genes (DEGs) between the 2 groups. We identified a total of 2,084 DEGs, of which 1,358 genes were upregulated and 726 genes were downregulated in the WES group compared with SES group. According to the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, the DEGs indicated the mammalian target of rapamycin signaling pathway, the Janus kinase-signal transducer and activator of transcription pathway, the mitogen‑activated protein kinase signaling pathway, and the insulin resistance pathways. Genes related to fatty liver disease were upregulated in WES group compared with SES group. In addition, expression of several genes associated with oxidative stress and bone resorption activity was altered in aged laying hens with different eggshell strength. Overall, these findings contribute to the identification of genes involved in different intensity of eggshell strength, enabling more understanding of the hepatic molecular mechanism underlying in decreased eggshell strength of aged laying hens.
Collapse
|
4
|
Oliveira CH, Dias KM, Bernardes RD, Diana TF, Rodrigueiro RJ, Calderano AA, Albino LF. The effects of arginine supplementation through different ratios of arginine:lysine on performance, skin quality and creatine levels of broiler chickens fed diets reduced in protein content. Poult Sci 2022; 101:102148. [PMID: 36152435 PMCID: PMC9508590 DOI: 10.1016/j.psj.2022.102148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/03/2022] [Accepted: 08/19/2022] [Indexed: 12/29/2022] Open
Abstract
Two trials were carried out to assess the effects of arginine supplementation through ratios of digestible arginine:lysine on growth performance, skin quality and creatine levels in muscle and serum of broiler chickens fed diets reduced in protein content. A total of 1,540 Cobb500 male chickens were distributed into 7 treatments, with 10 replicates with 22 birds each. The experimental diets were based on corn and soybean meal, and a control diet was formulated to satisfy broiler nutritional requirements. A basal diet with reduced protein content was formulated to meet broiler nutritional requirements, except for SID Arg levels. The experimental diets were obtained by adding L-arginine to basal diets, meeting 6 different SID Arg:Lys ratios (94, 100, 106, 112, 118, and 124%). Body weight, body weight gain, average daily feed intake, and feed conversion ratio were evaluated from 01 to 21 d old (trial 1) and from 22 to 44 d old (trial 2). At 21 and 44 d, in trials 1 and 2, respectively, birds were slaughtered to assess skin thickness (ST), skin strength (SS), creatine level in muscle (CRM) and serum (CRS). Data were subjected to ANOVA, and treatments were compared to the control group by Dunnett's test (P ≤ 0.05). Regression analyses were performed to model the variables assessed and the ratios of SID Arg:Lys. The SID Arg:Lys ratios did not affect ADFI of broilers in both trials (P > 0.05), whereas it linearly increased the BW, BWG, and ST, in both trials (P < 0.001). The FCR of broilers linearly decreased, in trial 1 (P = 0.038) and trial 2 (P < 0.001). The CRM of birds had a linear effect (P < 0.001) in trial 1, and a quadratic effect (P = 0.001) in trial 2. The CRS and SS of broilers linearly increased, in trial 2 (P < 0.001). In conclusion, increasing SID Arg:Lys ratios in diets reduced CP enhanced growth performance, skin quality and CR levels in muscle and serum of broiler chickens from 01 to 21 and 22 to 44 d old.
Collapse
Affiliation(s)
- Carlos H. Oliveira
- Department of Animal Science, Universidade Federal de Viçosa, 36570-900, Viçosa - MG, Brazil,Corresponding author:
| | - Kelly M.M. Dias
- Department of Animal Science, Universidade Federal de Viçosa, 36570-900, Viçosa - MG, Brazil
| | - Romário D. Bernardes
- Department of Animal Science, Universidade Federal de Viçosa, 36570-900, Viçosa - MG, Brazil
| | - Thiago F. Diana
- Department of Animal Science, Universidade Federal de Viçosa, 36570-900, Viçosa - MG, Brazil
| | | | - Arele A. Calderano
- Department of Animal Science, Universidade Federal de Viçosa, 36570-900, Viçosa - MG, Brazil
| | - Luiz F.T. Albino
- Department of Animal Science, Universidade Federal de Viçosa, 36570-900, Viçosa - MG, Brazil
| |
Collapse
|
5
|
Jobgen WS, Wu G. Dietary L-arginine supplementation increases the hepatic expression of AMP-activated protein kinase in rats. Amino Acids 2022; 54:1569-1584. [PMID: 35972553 DOI: 10.1007/s00726-022-03194-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 08/01/2022] [Indexed: 12/16/2022]
Abstract
The goal of this study was to elucidate the molecular mechanisms responsible for the anti-obesity effect of L-arginine supplementation in diet-induced obese rats. Male Sprague-Dawley rats were fed either a low-fat or high-fat diet for 15 weeks. Thereafter, lean or obese rats were pair-fed their same respective diets and received drinking water containing either 1.51% L-arginine-HCl or 2.55% L-alanine (isonitrogenous control) for 12 weeks. Gene and protein expression of key enzymes in the metabolism of energy substrates were determined using real-time polymerase-chain reaction and western blotting techniques. The mRNA levels of hepatic fatty acid synthase and stearoyl-CoA desaturase were reduced (P < 0.05) but those of hepatic AMP-activated protein kinase-α (AMPKα), peroxisome proliferator activator receptor γ coactivator-1α, and carnitine palmitoyltransferase I (CPT-I), as well as skeletal muscle CPT-I were increased (P < 0.05) by L-arginine treatment. The protein expression and activity of hepatic AMPKα markedly increased (P < 0.05) but the activity of hepatic acetyl-CoA carboxylase (ACC) decreased (P < 0.05) in response to dietary L-arginine supplementation. Collectively, our results indicate that liver is the major target for the action of dietary L-arginine supplementation on reducing white-fat mass in diet-induced obese rats by inhibiting fatty acid synthesis and increasing fatty acid oxidation via the AMPK-ACC signaling pathway. Additionally, increased CPT-I expression in skeletal muscle may also contribute to the enhanced oxidation of long-chain fatty acids in L-arginine-supplemented rats.
Collapse
Affiliation(s)
- Wenjuan S Jobgen
- Department of Animal Science and Faculty of Nutrition, Texas A&M University, College Station, TX, 77843, USA
| | - Guoyao Wu
- Department of Animal Science and Faculty of Nutrition, Texas A&M University, College Station, TX, 77843, USA.
| |
Collapse
|
6
|
Li W, Long X, Li F, Cao Y, Liu J, Fu S, Guo W, Hu G. Lysine stimulates the development of the murine mammary gland at puberty via PI3K/AKT/mTOR signalling axis. J Anim Physiol Anim Nutr (Berl) 2022; 106:1420-1430. [PMID: 35923149 DOI: 10.1111/jpn.13756] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/21/2022] [Accepted: 07/08/2022] [Indexed: 11/29/2022]
Abstract
Lysine is one of the essential amino acids. The effect of lysine on milk protein and milk fat anabolism has been reported, but the effect on mammary glands development has not been studied in detail. The normal development of the mammary glands at puberty is crucial to lactation of mammals. In this study, to explore the effect of lysine on mammary glands development, we fed different concentrations of lysine (0.025%, 0.05%, 0.1%) to pubertal mice and found that the addition of 0.1% lysine to drinking water significantly promoted mammary glands development. Furthermore, we treated mMECs (mouse mammary epithelial cells) with different concentrations of lysine (0, 0.2, 0.4, 0.6, 0.8 and 1 mM) to explore the underlying mechanism, and found that lysine promoted the proliferation of mMECs and development of mammary glands through PI3K/AKT/mTOR signalling pathway in pubertal mice. Overall, the results of this study revealed that lysine activated the PI3K/AKT/mTOR signal axis, elevated protein concentrations of cell proliferation markers, such as PCNA, Cyclin D1 and D3, and enhanced the proliferation of mMECs, finally promoted the murine mammary glands development at puberty.
Collapse
Affiliation(s)
- Wen Li
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Xiaoyu Long
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Feng Li
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Yu Cao
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Juxiong Liu
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Shoupeng Fu
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Wenjin Guo
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Guiqiu Hu
- Department of Theoretic Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| |
Collapse
|
7
|
Kumar N, Mandal CC. Cholesterol-Lowering Drugs on Akt Signaling for Prevention of Tumorigenesis. Front Genet 2021; 12:724149. [PMID: 34603386 PMCID: PMC8483559 DOI: 10.3389/fgene.2021.724149] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 08/23/2021] [Indexed: 12/12/2022] Open
Abstract
Cholesterol has been reported to be accumulated in cancer cells. The metabolic dysregulation of the cholesterol is associated with tumor development and progression. The cholesterol-lowering drugs have been found to be involved in the prevention and treatment of various cancers. Akt, a serine/threonine kinase, can modulate the role of several downstream proteins involved in cell proliferation, migration, invasion, metabolism, and apoptosis. Since its involvement in several signaling pathways, its dysregulation is commonly reported in several cancers. Thus, targeting Akt could be an effective approach for cancer prevention and therapy. Cholesterol-lowering drugs have been found to affect the expression of Akt, and its activation in the cancer cells and thus have shown anticancer activity in different type of cancers. These drugs act on various signaling pathways such as PTEN/Akt, PI3k/Akt, Akt/NF-κB, Akt/FOXO1, Akt/mTOR, etc., which will be discussed in this article. This review article will discuss the significance of cholesterol in cancer cells, cholesterol-lowering drugs, the role of Akt in cancer cells, and the effects of cholesterol-lowering drugs on Akt in the prevention of therapy resistance and metastasis.
Collapse
Affiliation(s)
- Navneet Kumar
- Department of Biochemistry, All India Institute of Medical Sciences, Bhopal, India
| | - Chandi C Mandal
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| |
Collapse
|
8
|
Kim KI, Baek JY, Chung YC, Nam JH, Shin WH, Jin BK. p70S6K on astrocytes protects dopamine neurons from 1-methyl-4-phenylpyridinium neurotoxicity. Glia 2021; 69:2133-2145. [PMID: 33956370 DOI: 10.1002/glia.24013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/16/2021] [Indexed: 12/17/2022]
Abstract
Our recent finding has demonstrated that astrocytes confer neuroprotection by endogenously producing ciliary neurotrophic factor (CNTF) via transient receptor potential vanilloid 1 (TRPV1) in Parkinson's disease (PD). In this study, the possible molecular target for TRPV1-mediated CNTF production and its neuroprotective effects on dopamine neurons were further investigated. For comparison, glial cell-line derived neurotrophic factor (GDNF) was also examined. The results show that TRPV1-ribosomal protein 70 S6 kinase (p70S6K) signaling on astrocytes produces endogenous CNTF in the SN of MPP+ -lesioned rat. By marked contrast, the expression of GDNF on astrocytes is independent of TRPV1-p70S6K signaling. Administration of a TRPV1 agonist, capsaicin, increases levels of phosphorylated p70S6K (p-p70S6K; activation of p70S6K) on astrocytes, resulting in the survival of dopamine neurons and behavioral recovery through endogenous production of CNTF in the MPP+ -lesioned rat model of PD. Immunohistochemical analysis reveals expression of p-p70S6K on astrocytes in the SN of PD patients, indicating relevance to human PD. The present in vivo data is the first to demonstrate that astrocytic TRPV1-p70S6K signaling plays a pivotal role as endogenous neuroprotective, and it may constitute a novel therapeutic target for treating PD.
Collapse
Affiliation(s)
- Kyoung In Kim
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, South Korea
| | - Jeong Yeob Baek
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, South Korea
| | - Young Cheul Chung
- Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, South Korea
| | - Jin Han Nam
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, South Korea
| | - Won-Ho Shin
- Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, South Korea
| | - Byung Kwan Jin
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, South Korea
| |
Collapse
|
9
|
Ezzati M, Velaei K, Kheirjou R. Melatonin and its mechanism of action in the female reproductive system and related malignancies. Mol Cell Biochem 2021; 476:3177-3190. [PMID: 33864572 DOI: 10.1007/s11010-021-04151-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 04/01/2021] [Indexed: 12/14/2022]
Abstract
Melatonin (N-acetyl-5-methoxytryptamine), the main product of pineal gland in vertebrates, is well known for its multifunctional role which has great influences on the reproductive system. Recent studies documented that melatonin is a powerful free radical scavenger that affects the reproductive system function and female infertility by MT1 and MT2 receptors. Furthermore, cancer researches indicate the influence of melatonin on the modulation of tumor cell signaling pathways resulting in growth inhibitor of the both in vivo/in vitro models. Cancer adjuvant therapy can also benefit from melatonin through therapeutic impact and decreasing the side effects of radiation and chemotherapy. This article reviews the scientific evidence about the influence of melatonin and its mechanism of action on the fertility potential, physiological alteration, and anticancer efficacy, during experimental and clinical studies.
Collapse
Affiliation(s)
- Maryam Ezzati
- Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran. .,Immunology Research Center, Tabriz University of Medical Sciences, PO. Box: 51376563833, Tabriz, Iran.
| | - Kobra Velaei
- Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Raziyeh Kheirjou
- Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| |
Collapse
|
10
|
Pu H, Heighes PT, Simpson F, Wang Y, Liang Z, Wischmeyer P, Hugh TJ, Doig GS. Early oral protein-containing diets following elective lower gastrointestinal tract surgery in adults: a meta-analysis of randomized clinical trials. Perioper Med (Lond) 2021; 10:10. [PMID: 33752757 PMCID: PMC7986268 DOI: 10.1186/s13741-021-00179-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 02/22/2021] [Indexed: 02/08/2023] Open
Abstract
Background Although current guidelines make consensus recommendations for the early resumption of oral intake after surgery, a recent comprehensive meta-analysis failed to identify any patient-centered benefits. We hypothesized this finding was attributable to pooling studies providing effective protein-containing diets with ineffective non-protein liquid diets. Therefore, the aim of this paper was to investigate the safety and efficacy of early oral protein-containing diets versus later (traditional) feeding after elective lower gastrointestinal tract surgery in adults. Methods PubMed, Embase, and the China National Knowledge Infrastructure databases were searched from inception until 1 August 2019. Reference lists of retrieved studies were hand searched to identify randomized clinical trials reporting mortality. No language restrictions were applied. Study selection, risk of bias appraisal and data abstraction were undertaken independently by two authors. Disagreements were settled by obtaining an opinion of a third author. Majority decisions prevailed. After assessment of underlying assumptions, a fixed-effects method was used for analysis. The primary outcome was mortality. Secondary outcomes included surgical site infections, postoperative nausea and vomiting, serious postoperative complications and other key measures of safety and efficacy. Results Eight randomized clinical trials recruiting 657 patients were included. Compared with later (traditional) feeding, commencing an early oral protein-containing diet resulted in a statistically significant reduction in mortality (odds ratio [OR] 0.31, P = 0.02, I2 = 0%). An early oral protein-containing diet also significantly reduced surgical site infections (OR 0.39, P = 0.002, I2 = 32%), postoperative nausea and vomiting (OR 0.62, P = 0.04, I2 = 37%), serious postoperative complications (OR 0.60, P = 0.01, I2 = 25%), and significantly improved other major outcomes. No harms attributable to an early oral protein-containing diet were identified. Conclusions The results of this systematic review can be used to upgrade current guideline statements to a grade A recommendation supporting an oral protein-containing diet commenced before the end of postoperative day 1 after elective lower gastrointestinal surgery in adults. Supplementary Information The online version contains supplementary material available at 10.1186/s13741-021-00179-3.
Collapse
Affiliation(s)
- Hong Pu
- Northern Clinical School Intensive Care Research Unit, Faculty of Medicine and Health, University of Sydney, Kolling Building-RNSH, Pacific Hwy, St Leonards, NSW, 2065, Australia.,Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, People's Republic of China
| | - Philippa T Heighes
- Northern Clinical School Intensive Care Research Unit, Faculty of Medicine and Health, University of Sydney, Kolling Building-RNSH, Pacific Hwy, St Leonards, NSW, 2065, Australia
| | - Fiona Simpson
- Northern Clinical School Intensive Care Research Unit, Faculty of Medicine and Health, University of Sydney, Kolling Building-RNSH, Pacific Hwy, St Leonards, NSW, 2065, Australia.,Nutrition Services, Royal North Shore Hospital, Sydney, Australia
| | - Yaoli Wang
- Northern Clinical School Intensive Care Research Unit, Faculty of Medicine and Health, University of Sydney, Kolling Building-RNSH, Pacific Hwy, St Leonards, NSW, 2065, Australia.,Department of Critical Care Medicine, Daping Hospital, Chongqing, People's Republic of China
| | - Zeping Liang
- Northern Clinical School Intensive Care Research Unit, Faculty of Medicine and Health, University of Sydney, Kolling Building-RNSH, Pacific Hwy, St Leonards, NSW, 2065, Australia.,Department of Critical Care Medicine, Daping Hospital, Chongqing, People's Republic of China
| | - Paul Wischmeyer
- Department of Anesthesiology and Surgery, Duke University, Durham, NC, USA
| | - Thomas J Hugh
- Upper GI Surgical Department, Royal North Shore Hospital and the University of Sydney, Sydney, Australia
| | - Gordon S Doig
- Northern Clinical School Intensive Care Research Unit, Faculty of Medicine and Health, University of Sydney, Kolling Building-RNSH, Pacific Hwy, St Leonards, NSW, 2065, Australia.
| |
Collapse
|
11
|
Li YL, Liu JL. Hypoosmolality impedes cytoophidium integrity during nitrogen starvation. Yeast 2021; 38:276-289. [PMID: 33294993 DOI: 10.1002/yea.3542] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 11/18/2020] [Accepted: 12/03/2020] [Indexed: 12/26/2022] Open
Abstract
CTP synthase (CTPS) cytoophidia have been found in many species over domains of life in the past 10 years, implying the evolutionary conservation of these structures. However, there are differences in cytoophidia between species. The difference in CTPS cytoophidium properties between budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) inspires this research. We study the effects of culture environment on cytoophidia in S. cerevisiae by switching to the optimal medium for S. pombe. S. cerevisiae CTPS cytoophidium fragmentation and pseudohyphae formation are observed after treatment with S. pombe medium YES instead of S. cerevisiae medium YPD. By modifying the level of each ingredient of the media, we find that hypoosmolality impedes cytoophidium integrity during nitrogen starvation. Our study demonstrates the relationship between cytoophidium integrity and environmental stress, supporting the role of cytoophidia in stress resistance.
Collapse
Affiliation(s)
- Yi-Lan Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Ji-Long Liu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| |
Collapse
|
12
|
Abstract
Abstract
Background
Organisms show an incredibly diverse array of body and organ shapes that are both unique to their taxon and important for adapting to their environment. Achieving these specific shapes involves coordinating the many processes that transform single cells into complex organs, and regulating their growth so that they can function within a fully-formed body.
Main text
Conceptually, body and organ shape can be separated in two categories, although in practice these categories need not be mutually exclusive. Body shape results from the extent to which organs, or parts of organs, grow relative to each other. The patterns of relative organ size are characterized using allometry. Organ shape, on the other hand, is defined as the geometric features of an organ’s component parts excluding its size. Characterization of organ shape is frequently described by the relative position of homologous features, known as landmarks, distributed throughout the organ. These descriptions fall into the domain of geometric morphometrics.
Conclusion
In this review, we discuss the methods of characterizing body and organ shape, the developmental programs thought to underlie each, highlight when and how the mechanisms regulating body and organ shape might overlap, and provide our perspective on future avenues of research.
Collapse
|
13
|
Chang S, Wang LHC, Chen BS. Investigating Core Signaling Pathways of Hepatitis B Virus Pathogenesis for Biomarkers Identification and Drug Discovery via Systems Biology and Deep Learning Method. Biomedicines 2020; 8:biomedicines8090320. [PMID: 32878239 PMCID: PMC7555687 DOI: 10.3390/biomedicines8090320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/19/2020] [Accepted: 08/21/2020] [Indexed: 12/17/2022] Open
Abstract
Hepatitis B Virus (HBV) infection is a major cause of morbidity and mortality worldwide. However, poor understanding of its pathogenesis often gives rise to intractable immune escape and prognosis recurrence. Thus, a valid systematic approach based on big data mining and genome-wide RNA-seq data is imperative to further investigate the pathogenetic mechanism and identify biomarkers for drug design. In this study, systems biology method was applied to trim false positives from the host/pathogen genetic and epigenetic interaction network (HPI-GEN) under HBV infection by two-side RNA-seq data. Then, via the principal network projection (PNP) approach and the annotation of KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, significant biomarkers related to cellular dysfunctions were identified from the core cross-talk signaling pathways as drug targets. Further, based on the pre-trained deep learning-based drug-target interaction (DTI) model and the validated pharmacological properties from databases, i.e., drug regulation ability, toxicity, and sensitivity, a combination of promising multi-target drugs was designed as a multiple-molecule drug to create more possibility for the treatment of HBV infection. Therefore, with the proposed systems medicine discovery and repositioning procedure, we not only shed light on the etiologic mechanism during HBV infection but also efficiently provided a potential drug combination for therapeutic treatment of Hepatitis B.
Collapse
Affiliation(s)
- Shen Chang
- Laboratory of Automatic Control, Signal Processing and Systems Biology, Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Lily Hui-Ching Wang
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Bor-Sen Chen
- Laboratory of Automatic Control, Signal Processing and Systems Biology, Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan;
- Correspondence:
| |
Collapse
|
14
|
Peroxisome Proliferator-Activated Receptors and Caloric Restriction-Common Pathways Affecting Metabolism, Health, and Longevity. Cells 2020; 9:cells9071708. [PMID: 32708786 PMCID: PMC7407644 DOI: 10.3390/cells9071708] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/14/2020] [Accepted: 07/14/2020] [Indexed: 02/06/2023] Open
Abstract
Caloric restriction (CR) is a traditional but scientifically verified approach to promoting health and increasing lifespan. CR exerts its effects through multiple molecular pathways that trigger major metabolic adaptations. It influences key nutrient and energy-sensing pathways including mammalian target of rapamycin, Sirtuin 1, AMP-activated protein kinase, and insulin signaling, ultimately resulting in reductions in basic metabolic rate, inflammation, and oxidative stress, as well as increased autophagy and mitochondrial efficiency. CR shares multiple overlapping pathways with peroxisome proliferator-activated receptors (PPARs), particularly in energy metabolism and inflammation. Consequently, several lines of evidence suggest that PPARs might be indispensable for beneficial outcomes related to CR. In this review, we present the available evidence for the interconnection between CR and PPARs, highlighting their shared pathways and analyzing their interaction. We also discuss the possible contributions of PPARs to the effects of CR on whole organism outcomes.
Collapse
|
15
|
Zeitz JO, Käding SC, Niewalda IR, Most E, Dorigam JCDP, Eder K. The influence of dietary leucine above recommendations and fixed ratios to isoleucine and valine on muscle protein synthesis and degradation pathways in broilers. Poult Sci 2020; 98:6772-6786. [PMID: 31250025 PMCID: PMC8913973 DOI: 10.3382/ps/pez396] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 06/13/2019] [Indexed: 01/30/2023] Open
Abstract
This study investigated the hypothesis that dietary supplementation of leucine (Leu) above actual recommendations activates protein synthesis and inhibits protein degradation pathways on the molecular level and supports higher muscle growth in broilers. Day-old male Cobb-500 broilers (n = 180) were allotted to 3 groups and phase-fed 3 different corn-wheat-soybean meal-based basal diets during periods 1 to 10, 11 to 21, and 22 to 35 D. The control group (L0) received the basal diet which met the broiler's requirements of nutrients and amino acids for maintenance and growth. Groups L1 and L2 received basal diets supplemented with Leu to exceed recommendations by 35 and 60%, respectively, and isoleucine (Ile) and valine (Val) were supplemented to keep Leu: Ile and Leu: Val ratios fixed. Samples of liver and breast muscle and pancreas were collected on days 10, 21, and 35. The gene expression and abundance of total and phosphorylated proteins involved in the mammalian target of rapamycin pathway of protein synthesis, in the ubiquitin-proteasome pathway and autophagy-lysosomal pathway of protein degradation, in the general control nonderepressible 2/eukaryotic translation initiation factor 2A pathway involved in the inhibition of protein synthesis, and in the myostatin-Smad2/3 pathway involved in myogenesis were evaluated in the muscle, as well as expression of genes involved in the growth hormone axis. Growth performance, feed intake, the feed conversion ratio, and carcass weights did not differ between the 3 groups (P > 0.05). Plasma concentrations of Leu, Ile, and Val and of their keto acids, and the activity of the branched-chain α-keto acid dehydrogenase in the pancreas increased dose dependently with increasing dietary Leu concentrations. In the breast muscle, relative mRNA abundances of genes and phosphorylation of selected proteins involved in all investigated pathways were largely uninfluenced by dietary Leu supplementation (P > 0.05). In summary, these data indicate that excess dietary Leu concentrations do not influence protein synthesis or degradation pathways, and subsequently do not increase muscle growth in broilers at fixed ratios to Ile and Val.
Collapse
Affiliation(s)
- Johanna O Zeitz
- Institute of Animal Nutrition and Nutritional Physiology, University of Giessen, Heinrich-Buff-Ring 26-32 (IFZ), D-35392 Giessen, Germany
| | - Stella-Christin Käding
- Institute of Animal Nutrition and Nutritional Physiology, University of Giessen, Heinrich-Buff-Ring 26-32 (IFZ), D-35392 Giessen, Germany
| | - Ines R Niewalda
- Institute of Animal Nutrition and Nutritional Physiology, University of Giessen, Heinrich-Buff-Ring 26-32 (IFZ), D-35392 Giessen, Germany
| | - Erika Most
- Institute of Animal Nutrition and Nutritional Physiology, University of Giessen, Heinrich-Buff-Ring 26-32 (IFZ), D-35392 Giessen, Germany
| | | | - Klaus Eder
- Institute of Animal Nutrition and Nutritional Physiology, University of Giessen, Heinrich-Buff-Ring 26-32 (IFZ), D-35392 Giessen, Germany
| |
Collapse
|
16
|
|
17
|
Sobieszczuk-Nowicka E, Paluch-Lubawa E, Mattoo AK, Arasimowicz-Jelonek M, Gregersen PL, Pacak A. Polyamines - A New Metabolic Switch: Crosstalk With Networks Involving Senescence, Crop Improvement, and Mammalian Cancer Therapy. FRONTIERS IN PLANT SCIENCE 2019; 10:859. [PMID: 31354753 PMCID: PMC6635640 DOI: 10.3389/fpls.2019.00859] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 06/14/2019] [Indexed: 05/06/2023]
Abstract
Polyamines (PAs) are low molecular weight organic cations comprising biogenic amines that play multiple roles in plant growth and senescence. PA metabolism was found to play a central role in metabolic and genetic reprogramming during dark-induced barley leaf senescence (DILS). Robust PA catabolism can impact the rate of senescence progression in plants. We opine that deciphering senescence-dependent polyamine-mediated multidirectional metabolic crosstalks is important to understand regulation and involvement of PAs in plant death and re-mobilization of nutrients during senescence. This will involve optimizing the use of PA biosynthesis inhibitors, robust transgenic approaches to modulate PA biosynthetic and catabolic genes, and developing novel germplasm enriched in pro- and anti-senescence traits to ensure sustained crop productivity. PA-mediated delay of senescence can extend the photosynthesis capacity, thereby increasing grain starch content in malting grains such as barley. On the other hand, accelerating the onset of senescence can lead to increases in mineral and nitrogen content in grains for animal feed. Unraveling the "polyamine metabolic switch" and delineating the roles of PAs in senescence should further our knowledge about autophagy mechanisms involved in plant senescence as well as mammalian systems. It is noteworthy that inhibitors of PA biosynthesis block cell viability in animal model systems (cell tumor lines) to control some cancers, in this instance, proliferative cancer cells were led toward cell death. Likewise, PA conjugates work as signal carriers for slow release of regulatory molecule nitric oxide in the targeted cells. Taken together, these and other outcomes provide examples for developing novel therapeutics for human health wellness as well as developing plant resistance/tolerance to stress stimuli.
Collapse
Affiliation(s)
- Ewa Sobieszczuk-Nowicka
- Department of Plant Physiology, Faculty of Biology, Institute of Experimental Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
| | - Ewelina Paluch-Lubawa
- Department of Plant Physiology, Faculty of Biology, Institute of Experimental Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
| | - Autar K. Mattoo
- Sustainable Agricultural Systems Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, United States Department of Agriculture, Beltsville, MD, United States
| | - Magdalena Arasimowicz-Jelonek
- Department of Plant Ecophysiology, Faculty of Biology, Institute of Experimental Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
| | - Per L. Gregersen
- Department of Molecular Biology and Genetics, Aarhus University, Slagelse, Denmark
| | - Andrzej Pacak
- Department of Gene Expression, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University in Poznań, Poznań, Poland
| |
Collapse
|
18
|
Jeung YJ, Lee K, Lee HJ, Kim E, Son MJ, Ahn J, Kim HG, Kim W, Lee HJ, Kim JM, Chung KS. Cationic amino acid transporter PQLC2 is a potential therapeutic target in gastric cancer. Cancer Sci 2019; 110:1453-1463. [PMID: 30729615 PMCID: PMC6447956 DOI: 10.1111/cas.13966] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 01/25/2019] [Accepted: 02/05/2019] [Indexed: 12/11/2022] Open
Abstract
Tumor cells overexpress amino acid transporters to meet the increased demand for amino acids. PQ loop repeat‐containing (PQLC)2 is a cationic amino acid transporter that might be involved in cancer progression. Here, we show that upregulation of PQLC2 is critical to gastric cancer (GC) development in vitro and in vivo. Both PQLC2 mRNA and protein were overexpressed in GC tissues, especially of the diffuse type. Overexpression of PQLC2 promoted cell growth, anchorage independence, and tumor formation in nude mice. This was due to activation of MEK/ERK1/2 and PI3K/AKT signaling. Conversely, PQLC2 knockdown caused growth arrest and cell death of cancer cells and suppressed tumor growth in a mouse xenograft model. These results suggest that targeting PQLC2 is an effective strategy for GC treatment.
Collapse
Affiliation(s)
- Yun-Ji Jeung
- Biomedical Translational Research Center, KRIBB, Daejeon, Korea.,Department of Pathology and Medical Science, Chungnam National University College of Medicine, Daejeon, Korea
| | - Kyeong Lee
- College of Pharmacy, Dongguk University-Seoul, Goyang, Korea
| | - Hyo Jin Lee
- Department of Internal Medicine, Chungnam National University College of Medicine, Daejeon, Korea
| | - Eunah Kim
- Stem Cell Convergence Research Center, KRIBB, Daejeon, Korea
| | - Myung Jin Son
- Stem Cell Convergence Research Center, KRIBB, Daejeon, Korea.,Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon, Korea
| | - Jiwon Ahn
- Biomedical Translational Research Center, KRIBB, Daejeon, Korea
| | - Han-Gyeul Kim
- Biomedical Translational Research Center, KRIBB, Daejeon, Korea.,Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon, Korea
| | - Wantae Kim
- Biomedical Translational Research Center, KRIBB, Daejeon, Korea
| | - Ho-Joon Lee
- Stem Cell Convergence Research Center, KRIBB, Daejeon, Korea
| | - Jin Man Kim
- Department of Internal Medicine, Chungnam National University College of Medicine, Daejeon, Korea
| | - Kyung-Sook Chung
- Biomedical Translational Research Center, KRIBB, Daejeon, Korea.,Stem Cell Convergence Research Center, KRIBB, Daejeon, Korea.,Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon, Korea
| |
Collapse
|
19
|
Boutouja F, Stiehm CM, Platta HW. mTOR: A Cellular Regulator Interface in Health and Disease. Cells 2019; 8:cells8010018. [PMID: 30609721 PMCID: PMC6356367 DOI: 10.3390/cells8010018] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 12/25/2018] [Accepted: 01/01/2019] [Indexed: 12/19/2022] Open
Abstract
The mechanistic target of Rapamycin (mTOR) is a ubiquitously-conserved serine/threonine kinase, which has a central function in integrating growth signals and orchestrating their physiologic effects on cellular level. mTOR is the core component of differently composed signaling complexes that differ in protein composition and molecular targets. Newly identified classes of mTOR inhibitors are being developed to block autoimmune diseases and transplant rejections but also to treat obesity, diabetes, and different types of cancer. Therefore, the selective and context-dependent inhibition of mTOR activity itself might come into the focus as molecular target to prevent severe diseases and possibly to extend life span. This review provides a general introduction to the molecular composition and physiologic function of mTOR complexes as part of the Special Issue “2018 Select Papers by Cells’ Editorial Board Members”.
Collapse
Affiliation(s)
- Fahd Boutouja
- Biochemie Intrazellulärer Transportprozesse, Ruhr-Universität Bochum, 44801 Bochum, Germany.
| | - Christian M Stiehm
- Biochemie Intrazellulärer Transportprozesse, Ruhr-Universität Bochum, 44801 Bochum, Germany.
| | - Harald W Platta
- Biochemie Intrazellulärer Transportprozesse, Ruhr-Universität Bochum, 44801 Bochum, Germany.
| |
Collapse
|
20
|
Counihan JL, Grossman EA, Nomura DK. Cancer Metabolism: Current Understanding and Therapies. Chem Rev 2018; 118:6893-6923. [DOI: 10.1021/acs.chemrev.7b00775] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Jessica L. Counihan
- Departments of Chemistry, Molecular and Cell Biology, and Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, California 94720, United States
| | - Elizabeth A. Grossman
- Departments of Chemistry, Molecular and Cell Biology, and Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, California 94720, United States
| | - Daniel K. Nomura
- Departments of Chemistry, Molecular and Cell Biology, and Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, California 94720, United States
| |
Collapse
|
21
|
A comparative analysis of single cell and droplet-based FACS for improving production phenotypes: Riboflavin overproduction in Yarrowia lipolytica. Metab Eng 2018; 47:346-356. [DOI: 10.1016/j.ymben.2018.04.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/02/2018] [Accepted: 04/20/2018] [Indexed: 12/15/2022]
|
22
|
Torinsson Naluai Å, Saadat Vafa L, Gudjonsdottir AH, Arnell H, Browaldh L, Nilsson S, Agardh D. Altered peripheral amino acid profile indicate a systemic impact of active celiac disease and a possible role of amino acids in disease pathogenesis. PLoS One 2018. [PMID: 29538446 PMCID: PMC5851604 DOI: 10.1371/journal.pone.0193764] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND We have previously performed a Genome Wide Association and linkage study that indicated a new disease triggering mechanism involving amino acid metabolism and nutrient sensing signaling pathways. OBJECTIVE The aim of this study was to investigate if plasma amino acid levels differed among children with celiac disease compared with disease controls. MATERIALS AND METHODS Fasting plasma samples from 141 children with celiac disease and 129 non-celiac disease controls, were analyzed for amino acid levels by liquid chromatography-tandem mass spectrometry (LC/MS). A general linear model using age and experimental effects as covariates was used to compare amino acid levels between children with a diagnosis of celiac disease and controls. RESULTS Seven out of twenty-three analyzed amino acids were elevated in children with celiac disease compared with controls (tryptophan, taurine, glutamic acid, proline, ornithine, alanine and methionine). The significance of the individual amino acids do not survive multiple correction, however, multivariate analyses of the amino acid profile showed significantly altered amino acid levels in children with celiac disease overall and after correction for age, sex and experimental effects (p = 8.4 × 10-8). CONCLUSION These findings support the idea that amino acids could influence systemic inflammation and play a possible role in disease pathogenesis.
Collapse
Affiliation(s)
- Åsa Torinsson Naluai
- Institute of Biomedicine, Department of Microbiology & Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- * E-mail:
| | - Ladan Saadat Vafa
- Institute of Biomedicine, Department of Microbiology & Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Audur H. Gudjonsdottir
- Institute of Clinical Sciences, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Henrik Arnell
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Karolinska University Hospital and Division of Pediatrics, CLINTEC, Karolinska Institute, Stockholm, Sweden
| | - Lars Browaldh
- Department of Clinical Science and Education, Karolinska Institute, Sodersjukhuset, Stockholm, Sweden
| | - Staffan Nilsson
- Department of Mathematical Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Daniel Agardh
- Diabetes & Celiac Disease Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden
| |
Collapse
|
23
|
The angiotensin II type 1 receptor antagonist telmisartan inhibits cell proliferation and tumor growth of esophageal adenocarcinoma via the AMPKα/mTOR pathway in vitro and in vivo. Oncotarget 2018; 8:8536-8549. [PMID: 28052030 PMCID: PMC5352420 DOI: 10.18632/oncotarget.14345] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 12/05/2016] [Indexed: 01/18/2023] Open
Abstract
Telmisartan, a widely used antihypertensive drug, is an angiotensin II type 1 (AT1) receptor blocker (ARB). This drug inhibits cancer cell proliferation, but the underlying mechanisms in various cancers, including esophageal cancer, remain unknown. The aim of the present study was to evaluate the effects of telmisartan on human esophageal cancer cell proliferation in vitro and in vivo. We assessed the effects of telmisartan on human esophageal adenocarcinoma (EAC) cells using the cell lines OE19, OE33, and SKGT-4. Telmisartan inhibited the proliferation of these three cell lines via blockade of the G0 to G1 cell cycle transition. This blockade was accompanied by a strong decrease in cyclin D1, cyclin E, and other cell cycle-related proteins. Notably, the AMP-activated protein kinase (AMPK) pathway, a fuel sensor signaling pathway, was enhanced by telmisartan. Compound C, which inhibits the two catalytic subunits of AMPK, enhanced the expression of cyclin E, leading to G0/G1 arrest in human EAC cells. In addition, telmisartan reduced the phosphorylation of epidermal growth factor receptor (p-EGFR) and ERBB2 in vitro. In our in vivo study, intraperitoneal injection of telmisartan led to a 73.2% reduction in tumor growth in mice bearing xenografts derived from OE19 cells. Furthermore, miRNA expression was significantly altered by telmisartan in vitro and in vivo. In conclusion, telmisartan suppressed human EAC cell proliferation and tumor growth by inducing cell cycle arrest via the AMPK/mTOR pathway.
Collapse
|
24
|
Oura K, Tadokoro T, Fujihara S, Morishita A, Chiyo T, Samukawa E, Yamana Y, Fujita K, Sakamoto T, Nomura T, Yoneyama H, Kobara H, Mori H, Iwama H, Okano K, Suzuki Y, Masaki T. Telmisartan inhibits hepatocellular carcinoma cell proliferation in vitro by inducing cell cycle arrest. Oncol Rep 2017; 38:2825-2835. [PMID: 29048654 PMCID: PMC5780034 DOI: 10.3892/or.2017.5977] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 08/28/2017] [Indexed: 12/22/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and the third leading cause of cancer-related death. Telmisartan, a widely used antihypertensive drug, is an angiotensin II type 1 (AT1) receptor blocker (ARB) that might inhibit cancer cell proliferation, but the mechanisms through which telmisartan affects various cancers remain unknown. The aim of the present study was to evaluate the effects of telmisartan on human HCC and to assess the expression of microRNAs (miRNAs). We studied the effects of telmisartan on HCC cells using the HLF, HLE, HepG2, HuH-7 and PLC/PRF/5 cell lines. In our experiments, telmisartan inhibited the proliferation of HLF, HLE and HepG2 cells, which represent poorly differentiated types of HCC cells. However, HuH-7 and PLC/PRF/5 cells, which represent well-differentiated types of HCC cells, were not sensitive to telmisartan. Telmisartan induced G0/G1 cell cycle arrest of HLF cells by inhibiting the G0-to-G1 cell cycle transition. This blockade was accompanied by a marked decrease in the levels of cyclin D1, cyclin E and other cell cycle-related proteins. Notably, the activity of the AMP-activated protein kinase (AMPK) pathway was increased, and the mammalian target of rapamycin (mTOR) pathway was inhibited by telmisartan treatment. Additionally, telmisartan increased the level of caspase-cleaved cytokeratin 18 (cCK18), partially contributed to the induction of apoptosis in HLF cells and reduced the phosphorylation of ErbB3 in HLF cells. Furthermore, miRNA expression was markedly altered by telmisartan in vitro. In conclusion, telmisartan inhibits human HCC cell proliferation by inducing cell cycle arrest.
Collapse
Affiliation(s)
- Kyoko Oura
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Tomoko Tadokoro
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Shintaro Fujihara
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Asahiro Morishita
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Taiga Chiyo
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Eri Samukawa
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Yoshimi Yamana
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Koji Fujita
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Teppei Sakamoto
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Takako Nomura
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Hirohito Yoneyama
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Hideki Kobara
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Hirohito Mori
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Hisakazu Iwama
- Life Science Research Center, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Keiichi Okano
- Gastroenterological Surgery, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Yasuyuki Suzuki
- Gastroenterological Surgery, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Tsutomu Masaki
- Department of Gastroenterology and Neurology, Faculty of Medicine/Graduate School of Medicine, Kagawa University, Kagawa 761-0793, Japan
| |
Collapse
|
25
|
Ariga M, Yoneyama Y, Fukushima T, Ishiuchi Y, Ishii T, Sato H, Hakuno F, Nedachi T, Takahashi SI. Glucose deprivation attenuates sortilin levels in skeletal muscle cells. Endocr J 2017; 64:255-268. [PMID: 27980238 DOI: 10.1507/endocrj.ej16-0319] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In skeletal muscle, sortilin plays a predominant role in the sorting of glucose transporter 4 (Glut4), thereby controlling glucose uptake. Moreover, our previous study suggested that the sortilin expression levels are also implicated in myogenesis. Despite the importance of sortilin in skeletal muscle, however, the regulation of sortilin expression has not been completely understood. In the present study, we analyzed if the sortilin expression is regulated by glucose in C2C12 myocytes and rat skeletal muscles in vivo. Sortilin protein expression was elevated upon C2C12 cell differentiation and was further enhanced in the presence of a high concentration of glucose. The gene expression and protein degradation of sortilin were not affected by glucose. On the other hand, rapamycin partially reduced sortilin induction by a high concentration of glucose, which suggested that sortilin translation could be regulated by glucose, at least in part. We also examined if the sortilin regulation by glucose was also observed in skeletal muscles that were obtained from fed or fasted rats. Sortilin expression in both gastrocnemius and extensor digitorum longus (EDL) muscle was significantly decreased by 17-18h of starvation. On the other hand, pathological levels of high blood glucose did not alter the sortilin expression in rat skeletal muscle. Overall, the present study suggests that sortilin protein levels are reduced under hypoglycemic conditions by post-transcriptional control in skeletal muscles.
Collapse
MESH Headings
- Adaptor Proteins, Vesicular Transport/agonists
- Adaptor Proteins, Vesicular Transport/genetics
- Adaptor Proteins, Vesicular Transport/metabolism
- Animals
- Blood Glucose/analysis
- Cell Differentiation
- Cell Line
- Diabetes Mellitus, Experimental/blood
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Down-Regulation/drug effects
- Fasting/metabolism
- Food Deprivation
- Glucose/metabolism
- Hindlimb
- Male
- Mechanistic Target of Rapamycin Complex 1
- Multiprotein Complexes/antagonists & inhibitors
- Multiprotein Complexes/metabolism
- Muscle Cells/cytology
- Muscle Cells/drug effects
- Muscle Cells/metabolism
- Muscle Cells/pathology
- Muscle, Skeletal/cytology
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Protein Kinase Inhibitors/pharmacology
- RNA, Messenger/metabolism
- Rats, Wistar
- Sirolimus/pharmacology
- TOR Serine-Threonine Kinases/antagonists & inhibitors
- TOR Serine-Threonine Kinases/metabolism
- Up-Regulation/drug effects
Collapse
Affiliation(s)
- Miyako Ariga
- Department of Animal Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Hashemzaei M, Entezari Heravi R, Rezaee R, Roohbakhsh A, Karimi G. Regulation of autophagy by some natural products as a potential therapeutic strategy for cardiovascular disorders. Eur J Pharmacol 2017; 802:44-51. [PMID: 28238768 DOI: 10.1016/j.ejphar.2017.02.038] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 02/22/2017] [Accepted: 02/22/2017] [Indexed: 01/09/2023]
Abstract
Autophagy is a lysosomal degradation process through which long-lived and misfolded proteins and organelles are sequestered, degraded by lysosomes, and recycled. Autophagy is an essential part of cardiomyocyte homeostasis and increases the survival of cells following cellular stress and starvation. Recent studies made clear that dysregulation of autophagy in the cardiovascular system leads to heart hypertrophy and failure. In this manner, autophagy seems to be an attractive target in the new treatment of cardiovascular diseases. Although limited activation of autophagy is generally considered to be cardioprotective, excessive autophagy leads to cell death and cardiac atrophy. Natural products such as resveratrol, berberine, and curcumin that are present in our diet, can trigger autophagy via canonical (Beclin-1-dependent) and non-canonical (Beclin-1-independent) pathways. The autophagy-modifying capacity of these compounds should be taken into consideration for designing novel therapeutic agents. This review focuses on the role of autophagy in the cardioprotective effects of these compounds.
Collapse
Affiliation(s)
- Mahmoud Hashemzaei
- Department of Pharmacodynamics and Toxicology, School of Pharmacy, Zabol University of Medical Sciences, Zabol, Iran
| | - Reza Entezari Heravi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Zabol University of Medical Sciences, Zabol, Iran
| | - Ramin Rezaee
- Department of Physiology and Pharmacology, School of Medicine, North Khorasan University of Medical Sciences, Bojnurd, Iran
| | - Ali Roohbakhsh
- Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Gholamreza Karimi
- Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
| |
Collapse
|
27
|
Li Y, Li F, Chen S, Duan Y, Guo Q, Wang W, Wen C, Yin Y. Protein-Restricted Diet Regulates Lipid and Energy Metabolism in Skeletal Muscle of Growing Pigs. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:9412-9420. [PMID: 27960278 DOI: 10.1021/acs.jafc.6b03959] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The aim of this work was to study the lipid metabolism and energy status of skeletal muscle of pigs as affected by dietary protein restriction. Eighteen growing pigs were distributed into three treatments, and each group was fed one of three levels (20, 17, and 14%) of crude protein (CP) diets. Our results showed that pigs fed the 20% CP had greater (P < 0.05) gain:feed and muscle weight than those fed the 14% CP, but no differences between the 20 and 17% CP treatments. Additionally, protein restriction tended to increase (P = 0.07) the content of intramuscular fat (IMF) and up-regulated (P < 0.05) expression of lipogenic-related genes. Energy status was changed and, concomitantly, AMP-activated protein kinase α pathway was inhibited by reducing the dietary protein level. These results indicate protein restriction could be useful to improve IMF content of pigs through regulating lipid metabolism and associated energy utilization in muscle.
Collapse
Affiliation(s)
- Yinghui Li
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture , Changsha, Hunan 410125, China
- University of Chinese Academy of Sciences , Beijing 10008, China
| | - Fengna Li
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture , Changsha, Hunan 410125, China
- Hunan Co-Innovation Center of Animal Production Safety, CICAPS, Hunan Collaborative Innovation Center for Utilization of Botanical Functional Ingredients , Changsha, Hunan 410128, China
| | - Shuai Chen
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture , Changsha, Hunan 410125, China
- University of Chinese Academy of Sciences , Beijing 10008, China
| | - Yehui Duan
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture , Changsha, Hunan 410125, China
- University of Chinese Academy of Sciences , Beijing 10008, China
| | - Qiuping Guo
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture , Changsha, Hunan 410125, China
- University of Chinese Academy of Sciences , Beijing 10008, China
| | - Wenlong Wang
- Laboratory of Animal Nutrition and Human Health, School of Biology, Hunan Normal University , Changsha, Hunan 410018, China
| | - Chaoyue Wen
- Laboratory of Animal Nutrition and Human Health, School of Biology, Hunan Normal University , Changsha, Hunan 410018, China
| | - Yulong Yin
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture , Changsha, Hunan 410125, China
- Laboratory of Animal Nutrition and Human Health, School of Biology, Hunan Normal University , Changsha, Hunan 410018, China
| |
Collapse
|
28
|
Li YH, Wei HK, Li FN, Kim SW, Wen CY, Duan YH, Guo QP, Wang WL, Liu HN, Yin YL. Regulation in free amino acid profile and protein synthesis pathway of growing pig skeletal muscles by low-protein diets for different time periods1,2. J Anim Sci 2016; 94:5192-5205. [DOI: 10.2527/jas.2016-0917] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Y. H. Li
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
- University of Chinese Academy of Sciences, Beijing 100039, China
- Nutrition Department of Animal Science, North Carolina State University, Raleigh 27695
| | - H. K. Wei
- College of Animal Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - F. N. Li
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
- Hunan Co-Innovation Center of Animal Production Safety, CICAPS; Hunan Collaborative Innovation Center for Utilization of Botanical Functional Ingredients, Changsha 410128, China
| | - S. W. Kim
- Nutrition Department of Animal Science, North Carolina State University, Raleigh 27695
| | - C. Y. Wen
- Laboratory of Animal Nutrition and Human Health, School of Biology, Hunan Normal University, Changsha Hunan 410018, China
| | - Y. H. Duan
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Q. P. Guo
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - W. L. Wang
- Laboratory of Animal Nutrition and Human Health, School of Biology, Hunan Normal University, Changsha Hunan 410018, China
| | - H. N. Liu
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
| | - Y. L. Yin
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
- Laboratory of Animal Nutrition and Human Health, School of Biology, Hunan Normal University, Changsha Hunan 410018, China
| |
Collapse
|
29
|
4EBP-Dependent Signaling Supports West Nile Virus Growth and Protein Expression. Viruses 2016; 8:v8100287. [PMID: 27763553 PMCID: PMC5086619 DOI: 10.3390/v8100287] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 09/16/2016] [Accepted: 10/07/2016] [Indexed: 12/24/2022] Open
Abstract
West Nile virus (WNV) is a (+) sense, single-stranded RNA virus in the Flavivirus genus. WNV RNA possesses an m7GpppNm 5' cap with 2'-O-methylation that mimics host mRNAs preventing innate immune detection and allowing the virus to translate its RNA genome through the utilization of cap-dependent translation initiation effectors in a wide variety of host species. Our prior work established the requirement of the host mammalian target of rapamycin complex 1 (mTORC1) for optimal WNV growth and protein expression; yet, the roles of the downstream effectors of mTORC1 in WNV translation are unknown. In this study, we utilize gene deletion mutants in the ribosomal protein kinase called S6 kinase (S6K) and eukaryotic translation initiation factor 4E-binding protein (4EBP) pathways downstream of mTORC1 to define the role of mTOR-dependent translation initiation signals in WNV gene expression and growth. We now show that WNV growth and protein expression are dependent on mTORC1 mediated-regulation of the eukaryotic translation initiation factor 4E-binding protein/eukaryotic translation initiation factor 4E-binding protein (4EBP/eIF4E) interaction and eukaryotic initiation factor 4F (eIF4F) complex formation to support viral growth and viral protein expression. We also show that the canonical signals of mTORC1 activation including ribosomal protein s6 (rpS6) and S6K phosphorylation are not required for WNV growth in these same conditions. Our data suggest that the mTORC1/4EBP/eIF4E signaling axis is activated to support the translation of the WNV genome.
Collapse
|
30
|
Manifava M, Smith M, Rotondo S, Walker S, Niewczas I, Zoncu R, Clark J, Ktistakis NT. Dynamics of mTORC1 activation in response to amino acids. eLife 2016; 5. [PMID: 27725083 PMCID: PMC5059141 DOI: 10.7554/elife.19960] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 09/07/2016] [Indexed: 12/12/2022] Open
Abstract
Amino acids are essential activators of mTORC1 via a complex containing RAG GTPases, RAGULATOR and the vacuolar ATPase. Sensing of amino acids causes translocation of mTORC1 to lysosomes, an obligate step for activation. To examine the spatial and temporal dynamics of this translocation, we used live imaging of the mTORC1 component RAPTOR and a cell permeant fluorescent analogue of di-leucine methyl ester. Translocation to lysosomes is a transient event, occurring within 2 min of aa addition and peaking within 5 min. It is temporally coupled with fluorescent leucine appearance in lysosomes and is sustained in comparison to aa stimulation. Sestrin2 and the vacuolar ATPase are negative and positive regulators of mTORC1 activity in our experimental system. Of note, phosphorylation of canonical mTORC1 targets is delayed compared to lysosomal translocation suggesting a dynamic and transient passage of mTORC1 from the lysosomal surface before targetting its substrates elsewhere. DOI:http://dx.doi.org/10.7554/eLife.19960.001 Cells in all organisms must constantly measure the amount of nutrients available to them in order to be healthy and grow properly. For example, cells use a complex sensing system to measure how many amino acids – the building blocks of proteins – are available to them. One enzyme called mTOR alerts the cell to amino acid levels. When amino acids are available, mTOR springs into action and turns on the production of proteins in the cell. However, when amino acids are scarce, mTOR turns off, which slows down protein production and causes the cell to begin scavenging amino acids by digesting parts of itself. Studies of mTOR have shown that the protein cannot turn on until it visits the surface of small sacks in the cell called lysosomes. These are the major sites within cell where proteins and other molecules are broken down. Scientists know how mTOR gets to the lysosomes, but not how quickly the process occurs. Now, Manifava, Smith et al. have used microscopes to record live video of the mTOR enzyme as it interacts with amino acids revealing the whole process takes place in just a few minutes. In the experiments, a fluorescent tag was added to part of mTOR to make the protein visible under a microscope. The video showed that, in human cells supplied with amino acids, mTOR reaches the lysosomes within 2 minutes of the amino acids becoming available. Then, within 3-4 minutes the mTOR turns on and leaves the lysosome. Even though the mTOR has left the lysosome, it somehow remembers that amino acids are available and stays active. The experiments show that mTOR’s brief interaction with the lysosome switches it on and keeps it on even after mTOR leaves. Future studies will be needed to determine exactly how mTOR remembers its interaction with the lysosome and stays active afterwards. DOI:http://dx.doi.org/10.7554/eLife.19960.002
Collapse
Affiliation(s)
- Maria Manifava
- Signalling Programme, Babraham Institute, Cambridge, United Kingdom
| | - Matthew Smith
- Signalling Programme, Babraham Institute, Cambridge, United Kingdom
| | - Sergio Rotondo
- Signalling Programme, Babraham Institute, Cambridge, United Kingdom
| | - Simon Walker
- Signalling Programme, Babraham Institute, Cambridge, United Kingdom
| | | | - Roberto Zoncu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Jonathan Clark
- Signalling Programme, Babraham Institute, Cambridge, United Kingdom
| | | |
Collapse
|
31
|
Zhou Y, Ren J, Song T, Peng J, Wei H. Methionine Regulates mTORC1 via the T1R1/T1R3-PLCβ-Ca 2+-ERK1/2 Signal Transduction Process in C2C12 Cells. Int J Mol Sci 2016; 17:ijms17101684. [PMID: 27727170 PMCID: PMC5085716 DOI: 10.3390/ijms17101684] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 09/20/2016] [Accepted: 09/27/2016] [Indexed: 12/13/2022] Open
Abstract
The mammalian target of rapamycin complex 1 (mTORC1) integrates amino acid (AA) availability to support protein synthesis and cell growth. Taste receptor type 1 member (T1R) is a G protein-coupled receptor that functions as a direct sensor of extracellular AA availability to regulate mTORC1 through Ca2+ stimulation and extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation. However, the roles of specific AAs in T1R1/T1R3-regulated mTORC1 are poorly defined. In this study, T1R1 and T1R3 subunits were expressed in C2C12 myotubes, and l-AA sensing was accomplished by T1R1/T1R3 to activate mTORC1. In response to l-AAs, such as serine (Ser), arginine (Arg), threonine (Thr), alanine (Ala), methionine (Met), glutamine (Gln), and glycine (Gly), Met induced mTORC1 activation and promoted protein synthesis. Met also regulated mTORC1 via T1R1/T1R3-PLCβ-Ca2+-ERK1/2 signal transduction. Results revealed a new role for Met-regulated mTORC1 via an AA receptor. Further studies should be performed to determine the role of T1R1/T1R3 in mediating extracellular AA to regulate mTOR signaling and to reveal its mechanism.
Collapse
Affiliation(s)
- Yuanfei Zhou
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agriculture University, Wuhan 430070, Hubei, China.
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, Hubei, China.
| | - Jiao Ren
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agriculture University, Wuhan 430070, Hubei, China.
| | - Tongxing Song
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agriculture University, Wuhan 430070, Hubei, China.
| | - Jian Peng
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agriculture University, Wuhan 430070, Hubei, China.
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, Hubei, China.
| | - Hongkui Wei
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agriculture University, Wuhan 430070, Hubei, China.
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, Hubei, China.
| |
Collapse
|
32
|
Gill KS, Fernandes P, O'Donovan TR, McKenna SL, Doddakula KK, Power DG, Soden DM, Forde PF. Glycolysis inhibition as a cancer treatment and its role in an anti-tumour immune response. Biochim Biophys Acta Rev Cancer 2016; 1866:87-105. [PMID: 27373814 DOI: 10.1016/j.bbcan.2016.06.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 06/29/2016] [Accepted: 06/30/2016] [Indexed: 12/23/2022]
Abstract
Increased glycolysis is the main source of energy supply in cancer cells that use this metabolic pathway for ATP generation. Altered energy metabolism is a biochemical fingerprint of cancer cells that represents one of the "hallmarks of cancer". The immune system can prevent tumour growth by eliminating cancer cells but this editing process ultimately results in poorly immunogenic cells remaining allowing for unchallenged tumour growth. In this review we look at the glycolysis pathway as a target for cancer treatments. We also examine the interplay between the glycolysis modulation and the immune response as an anti-cancer therapy.
Collapse
Affiliation(s)
- Kheshwant S Gill
- Cork Cancer Research Centre, Western Gateway Building, University College Cork, Cork, Ireland; Cardiothoracic Surgery Department, Cork University Hospital, Cork, Ireland
| | - Philana Fernandes
- Cork Cancer Research Centre, Western Gateway Building, University College Cork, Cork, Ireland
| | - Tracey R O'Donovan
- Cork Cancer Research Centre, Western Gateway Building, University College Cork, Cork, Ireland
| | - Sharon L McKenna
- Cork Cancer Research Centre, Western Gateway Building, University College Cork, Cork, Ireland
| | | | - Derek G Power
- Cork Cancer Research Centre, Western Gateway Building, University College Cork, Cork, Ireland; Department of Medical Oncology, Mercy University Hospital, Grenville Place, Cork, Ireland
| | - Declan M Soden
- Cork Cancer Research Centre, Western Gateway Building, University College Cork, Cork, Ireland
| | - Patrick F Forde
- Cork Cancer Research Centre, Western Gateway Building, University College Cork, Cork, Ireland.
| |
Collapse
|
33
|
Jiang WD, Qu B, Feng L, Jiang J, Kuang SY, Wu P, Tang L, Tang WN, Zhang YA, Zhou XQ, Liu Y. Histidine Prevents Cu-Induced Oxidative Stress and the Associated Decreases in mRNA from Encoding Tight Junction Proteins in the Intestine of Grass Carp (Ctenopharyngodon idella). PLoS One 2016; 11:e0157001. [PMID: 27280406 PMCID: PMC4900568 DOI: 10.1371/journal.pone.0157001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 05/22/2016] [Indexed: 01/14/2023] Open
Abstract
Copper (Cu) is a common heavy metal pollutant in aquatic environments that originates from natural as well as anthropogenic sources. The present study investigated whether Cu causes oxidative damage and induces changes in the expression of genes that encode tight junction (TJ) proteins, cytokines and antioxidant-related genes in the intestine of the grass carp (Ctenopharyngodon idella). We demonstrated that Cu decreases the survival rate of fish and increases oxidative damage as measured by increases in malondialdehyde and protein carbonyl contents. Cu exposure significantly decreased the expression of genes that encode the tight junction proteins, namely, claudin (CLDN)-c, -3 and -15 as well as occludin and zonula occludens-1, in the intestine of fish. In addition, Cu exposure increases the mRNA levels of the pro-inflammatory cytokines, specifically, IL-8, TNF-α and its related signalling factor (nuclear factor kappa B, NF-κB), which was partly correlated to the decreased mRNA levels of NF-κB inhibitor protein (IκB). These changes were associated with Cu-induced oxidative stress detected by corresponding decreases in glutathione (GSH) content, as well as decreases in the copper, zinc-superoxide dismutase (SOD1) and glutathione peroxidase (GPx) activities and mRNA levels, which were associated with the down-regulated antioxidant signalling factor NF-E2-related factor-2 (Nrf2) mRNA levels, and the Kelch-like-ECH-associated protein1 (Keap1) mRNA levels in the intestine of fish. Histidine supplementation in diets (3.7 up to 12.2 g/kg) blocked Cu-induced changes. These results indicated that Cu-induced decreases in intestinal TJ proteins and cytokine mRNA levels might be partially mediated by oxidative stress and are prevented by histidine supplementation in fish diet.
Collapse
Affiliation(s)
- Wei-Dan Jiang
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Biao Qu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Lin Feng
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Jun Jiang
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Sheng-Yao Kuang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, 610066, Chengdu, China
| | - Pei Wu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Ling Tang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, 610066, Chengdu, China
| | - Wu-Neng Tang
- Animal Nutrition Institute, Sichuan Academy of Animal Science, 610066, Chengdu, China
| | - Yong-An Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Xiao-Qiu Zhou
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Yang Liu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| |
Collapse
|
34
|
Moskalev A, Chernyagina E, Tsvetkov V, Fedintsev A, Shaposhnikov M, Krut'ko V, Zhavoronkov A, Kennedy BK. Developing criteria for evaluation of geroprotectors as a key stage toward translation to the clinic. Aging Cell 2016; 15:407-15. [PMID: 26970234 PMCID: PMC4854916 DOI: 10.1111/acel.12463] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/16/2016] [Indexed: 01/15/2023] Open
Abstract
In the coming decades, a massive shift in the aging segment of the population will have major social and economic consequences around the world. One way to offset this increase is to expedite the development of geroprotectors, substances that slow aging, repair age‐associated damage and extend healthy lifespan, or healthspan. While over 200 geroprotectors are now reported in model organisms and some are in human use for specific disease indications, the path toward determining whether they affect aging in humans remains obscure. Translation to the clinic is hampered by multiple issues including absence of a common set of criteria to define, select, and classify these substances, given the complexity of the aging process and their enormous diversity in mechanism of action. Translational research efforts would benefit from the formation of a scientific consensus on the following: the definition of ‘geroprotector’, the selection criteria for geroprotectors, a comprehensive classification system, and an analytical model. Here, we review current approaches to selection and put forth our own suggested selection criteria. Standardizing selection of geroprotectors will streamline discovery and analysis of new candidates, saving time and cost involved in translation to clinic.
Collapse
Affiliation(s)
- Alexey Moskalev
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences Moscow 119991 Russia
- Institute of Biology of Komi Science Center of Ural Branch of Russian Academy of Sciences Syktyvkar 167982 Russia
- Moscow Institute of Physics and Technology Dolgoprudny 141700 Russia
| | | | - Vasily Tsvetkov
- Moscow Institute of Physics and Technology Dolgoprudny 141700 Russia
- The Research Institute for Translational Medicine Pirogov Russian National Research Medical University Moscow 117997 Russia
| | - Alexander Fedintsev
- Institute of Biology of Komi Science Center of Ural Branch of Russian Academy of Sciences Syktyvkar 167982 Russia
| | - Mikhail Shaposhnikov
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences Moscow 119991 Russia
| | - Vyacheslav Krut'ko
- Institute for Systems Analysis Russian Academy of Sciences Moscow 117312 Russia
| | - Alex Zhavoronkov
- Institute of Biology of Komi Science Center of Ural Branch of Russian Academy of Sciences Syktyvkar 167982 Russia
- D. Rogachev FRC Center for Pediatric Hematology, Oncology and Immunology Samory Machela 1 Moscow 117997 Russia
- The Biogerontology Research Foundation 2354 Chynoweth House, Trevissome Park, Blackwater, Truro Cornwall TR4 8UN UK
| | | |
Collapse
|
35
|
Alanyl-glutamine supplementation regulates mTOR and ubiquitin proteasome proteolysis signaling pathways in piglets. Nutrition 2016; 32:1123-31. [PMID: 27155955 DOI: 10.1016/j.nut.2016.02.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 02/03/2016] [Accepted: 02/25/2016] [Indexed: 10/22/2022]
Abstract
OBJECTIVE The aim of the present study was to investigate the effects of the alanyl-glutamine dipeptide (Ala-Gln) or the combination supplementation of free alanine and glutamine (Ala+Gln) on the mammalian target of rapamycin (mTOR) and ubiquitin-proteasome proteolysis (UPP) signaling pathways in piglets. METHODS We randomly allocated 180 piglets to three treatments with three replicates of 20 piglets each, fed with diets containing 0.62% Ala, 0.5% Ala-Gln, 0.21% Ala+0.34% Gln, respectively. The duration of the experiment was 28 d. RESULTS The results showed that Ala-Gln increased average daily gain of piglets, and decreased the ratio of feed to gain (P < 0.05). Ala-Gln supplementation increased the concentrations of Gln and glutamate and decreased the activity of glutamine synthetase in liver and skeletal muscle (P < 0.05). Ala-Gln increased the expression of glutaminase and glutamate dehydrogenate (P < 0.05). The increased phosphorylation of eIF-4 E binding protein 1 (4E-BP1) and ribosomal protein S6 kinase 1 (S6K1) in Ala-Gln treatment were associated with phosphorylation of the mTOR in liver and skeletal muscle. Ala+Gln did not affect the phosphorylation abundances of mTOR, 4E-BP1, or S6K1 (P > 0.05). Ala-Gln supplementation inhibited the mRNA expressions of MAFbx and MuRF1 in skeletal muscle of piglets (P < 0.05). CONCLUSION Taken together, Ala-Gln supplementation improved the growth performance of piglets, enhanced the metabolism of Gln, upregulated protein synthetic signaling in liver and skeletal muscle and decreased protein degradative signaling in muscle of piglets. Moreover, these effects of Ala-Gln were more effective than those of Ala+Gln.
Collapse
|
36
|
Structure–activity relations of leucine derivatives reveal critical moieties for cellular uptake and activation of mTORC1-mediated signaling. Amino Acids 2016; 48:1045-1058. [DOI: 10.1007/s00726-015-2158-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Accepted: 12/16/2015] [Indexed: 01/21/2023]
|
37
|
Teixeira V, Costa V. Unraveling the role of the Target of Rapamycin signaling in sphingolipid metabolism. Prog Lipid Res 2015; 61:109-33. [PMID: 26703187 DOI: 10.1016/j.plipres.2015.11.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 11/04/2015] [Accepted: 11/09/2015] [Indexed: 02/06/2023]
Abstract
Sphingolipids are important bioactive molecules that regulate basic aspects of cellular metabolism and physiology, including cell growth, adhesion, migration, senescence, apoptosis, endocytosis, and autophagy in yeast and higher eukaryotes. Since they have the ability to modulate the activation of several proteins and signaling pathways, variations in the relative levels of different sphingolipid species result in important changes in overall cellular functions and fate. Sphingolipid metabolism and their route of synthesis are highly conserved from yeast to mammalian cells. Studies using the budding yeast Saccharomyces cerevisiae have served in many ways to foster our understanding of sphingolipid dynamics and their role in the regulation of cellular processes. In the past decade, studies in S. cerevisiae have unraveled a functional association between the Target of Rapamycin (TOR) pathway and sphingolipids, showing that both TOR Complex 1 (TORC1) and TOR Complex 2 (TORC2) branches control temporal and spatial aspects of sphingolipid metabolism in response to physiological and environmental cues. In this review, we report recent findings in this emerging and exciting link between the TOR pathway and sphingolipids and implications in human health and disease.
Collapse
Affiliation(s)
- Vitor Teixeira
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC, Instituto de Biologia Molecular e Celular, Porto, Portugal; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Departamento de Biologia Molecular, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Vítor Costa
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC, Instituto de Biologia Molecular e Celular, Porto, Portugal; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Departamento de Biologia Molecular, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| |
Collapse
|
38
|
Peters TW, Miller AW, Tourette C, Agren H, Hubbard A, Hughes RE. Genomic Analysis of ATP Efflux in Saccharomyces cerevisiae. G3 (BETHESDA, MD.) 2015; 6:161-70. [PMID: 26585826 PMCID: PMC4704715 DOI: 10.1534/g3.115.023267] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 11/06/2015] [Indexed: 01/12/2023]
Abstract
Adenosine triphosphate (ATP) plays an important role as a primary molecule for the transfer of chemical energy to drive biological processes. ATP also functions as an extracellular signaling molecule in a diverse array of eukaryotic taxa in a conserved process known as purinergic signaling. Given the important roles of extracellular ATP in cell signaling, we sought to comprehensively elucidate the pathways and mechanisms governing ATP efflux from eukaryotic cells. Here, we present results of a genomic analysis of ATP efflux from Saccharomyces cerevisiae by measuring extracellular ATP levels in cultures of 4609 deletion mutants. This screen revealed key cellular processes that regulate extracellular ATP levels, including mitochondrial translation and vesicle sorting in the late endosome, indicating that ATP production and transport through vesicles are required for efflux. We also observed evidence for altered ATP efflux in strains deleted for genes involved in amino acid signaling, and mitochondrial retrograde signaling. Based on these results, we propose a model in which the retrograde signaling pathway potentiates amino acid signaling to promote mitochondrial respiration. This study advances our understanding of the mechanism of ATP secretion in eukaryotes and implicates TOR complex 1 (TORC1) and nutrient signaling pathways in the regulation of ATP efflux. These results will facilitate analysis of ATP efflux mechanisms in higher eukaryotes.
Collapse
Affiliation(s)
| | - Aaron W Miller
- The Buck Institute for Research on Aging, Novato, California 94945
| | | | - Hannah Agren
- The Buck Institute for Research on Aging, Novato, California 94945
| | - Alan Hubbard
- School of Public Health, Division of Biostatistics, University of California, Berkeley, California 94729-7358
| | - Robert E Hughes
- The Buck Institute for Research on Aging, Novato, California 94945
| |
Collapse
|
39
|
Meijer AJ, Lorin S, Blommaart EF, Codogno P. Regulation of autophagy by amino acids and MTOR-dependent signal transduction. Amino Acids 2015; 47:2037-63. [PMID: 24880909 PMCID: PMC4580722 DOI: 10.1007/s00726-014-1765-4] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Accepted: 05/12/2014] [Indexed: 01/05/2023]
Abstract
Amino acids not only participate in intermediary metabolism but also stimulate insulin-mechanistic target of rapamycin (MTOR)-mediated signal transduction which controls the major metabolic pathways. Among these is the pathway of autophagy which takes care of the degradation of long-lived proteins and of the elimination of damaged or functionally redundant organelles. Proper functioning of this process is essential for cell survival. Dysregulation of autophagy has been implicated in the etiology of several pathologies. The history of the studies on the interrelationship between amino acids, MTOR signaling and autophagy is the subject of this review. The mechanisms responsible for the stimulation of MTOR-mediated signaling, and the inhibition of autophagy, by amino acids have been studied intensively in the past but are still not completely clarified. Recent developments in this field are discussed.
Collapse
Affiliation(s)
- Alfred J Meijer
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands.
| | - Séverine Lorin
- UPRES EA4530, Université Paris-Sud, Faculté de Pharmacie, 5 rue Jean-Baptiste Clément, 92296, Châtenay-Malabry Cedex, France
| | - Edward F Blommaart
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Patrice Codogno
- INSERM U1151-CNRS UMR 8253, Université Paris Descartes, 14 rue Maria Helena Vieira Da Silva CS61431, 75993, Paris Cedex 14, France
| |
Collapse
|
40
|
de Cavanagh EMV, Inserra F, Ferder L. Angiotensin II blockade: how its molecular targets may signal to mitochondria and slow aging. Coincidences with calorie restriction and mTOR inhibition. Am J Physiol Heart Circ Physiol 2015; 309:H15-44. [PMID: 25934099 DOI: 10.1152/ajpheart.00459.2014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 04/30/2015] [Indexed: 02/07/2023]
Abstract
Caloric restriction (CR), renin angiotensin system blockade (RAS-bl), and rapamycin-mediated mechanistic target of rapamycin (mTOR) inhibition increase survival and retard aging across species. Previously, we have summarized CR and RAS-bl's converging effects, and the mitochondrial function changes associated with their physiological benefits. mTOR inhibition and enhanced sirtuin and KLOTHO signaling contribute to the benefits of CR in aging. mTORC1/mTORC2 complexes contribute to cell growth and metabolic regulation. Prolonged mTORC1 activation may lead to age-related disease progression; thus, rapamycin-mediated mTOR inhibition and CR may extend lifespan and retard aging through mTORC1 interference. Sirtuins by deacetylating histone and transcription-related proteins modulate signaling and survival pathways and mitochondrial functioning. CR regulates several mammalian sirtuins favoring their role in aging regulation. KLOTHO/fibroblast growth factor 23 (FGF23) contribute to control Ca(2+), phosphate, and vitamin D metabolism, and their dysregulation may participate in age-related disease. Here we review how mTOR inhibition extends lifespan, how KLOTHO functions as an aging suppressor, how sirtuins mediate longevity, how vitamin D loss may contribute to age-related disease, and how they relate to mitochondrial function. Also, we discuss how RAS-bl downregulates mTOR and upregulates KLOTHO, sirtuin, and vitamin D receptor expression, suggesting that at least some of RAS-bl benefits in aging are mediated through the modulation of mTOR, KLOTHO, and sirtuin expression and vitamin D signaling, paralleling CR actions in age retardation. Concluding, the available evidence endorses the idea that RAS-bl is among the interventions that may turn out to provide relief to the spreading issue of age-associated chronic disease.
Collapse
Affiliation(s)
- Elena M V de Cavanagh
- Center of Hypertension, Cardiology Department, Austral University Hospital, Derqui, Argentina; School of Biomedical Sciences, Austral University, Buenos Aires, Argentina; and
| | - Felipe Inserra
- Center of Hypertension, Cardiology Department, Austral University Hospital, Derqui, Argentina; School of Biomedical Sciences, Austral University, Buenos Aires, Argentina; and
| | - León Ferder
- Department of Physiology and Pharmacology, Ponce School of Medicine, Ponce, Puerto Rico
| |
Collapse
|
41
|
Yuan C, Ding Y, He Q, Azzam MMM, Lu JJ, Zou XT. L-arginine upregulates the gene expression of target of rapamycin signaling pathway and stimulates protein synthesis in chicken intestinal epithelial cells. Poult Sci 2015; 94:1043-51. [PMID: 25771531 DOI: 10.3382/ps/pev051] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2014] [Indexed: 12/21/2022] Open
Abstract
L-arginine (Arg) is an indispensable amino acid in avians and is required for growth. The aim of this study was to investigate the effects of L-Arg on protein synthesis and genes expression involved in target of rapamycin (TOR) signaling pathway in chicken enterocytes. Cells were cultured for 4 days in L-Arg-free Dulbecco's modified Eagle's medium containing 10, 100, 200, 400, or 600 μM L-Arg. Cell growth, cell cycle, protein synthesis, and protein degradation as well as mRNA expression levels of TOR, ribosomal protein S6 kinase 1 (S6K1), and eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) were determined. The results showed that cell viability was enhanced by L-Arg with a maximal response at 10 to 400 μM. Increasing extracellular concentrations of L-Arg from 10 to 400 μM increased the cells in S and G2/M phase to a significant extent and decreased cell numbers in G0/G1 phase. Further more, addition of 100, 200, or 400 μM L-Arg to culture medium increased protein synthesis and reduced protein degradation in chicken intestinal epithelial cells. Consistent with the data on cell growth and protein turnover, supplementation of 100, 200, or 400 μM L-Arg increased the mRNA abundances of TOR, 4E-BP1, and S6K1. It was concluded the action of L-Arg involves in upregulating the genes expression of TOR cell signaling pathway which increases protein synthesis and reduces protein degradation.
Collapse
Affiliation(s)
- C Yuan
- Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou, China 310058
| | - Y Ding
- Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou, China 310058
| | - Qiang He
- Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou, China 310058
| | - M M M Azzam
- Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou, China 310058 Poultry Production Department, Mansoura University, Mansoura 35516, Egypt
| | - J J Lu
- Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou, China 310058
| | - X T Zou
- Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou, China 310058
| |
Collapse
|
42
|
Zheng X, Liang Y, He Q, Yao R, Bao W, Bao L, Wang Y, Wang Z. Current models of mammalian target of rapamycin complex 1 (mTORC1) activation by growth factors and amino acids. Int J Mol Sci 2014; 15:20753-69. [PMID: 25402640 PMCID: PMC4264194 DOI: 10.3390/ijms151120753] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 09/24/2014] [Accepted: 10/29/2014] [Indexed: 01/09/2023] Open
Abstract
Mammalian target of rapamycin (mTOR), which is now referred to as mechanistic target of rapamycin, integrates many signals, including those from growth factors, energy status, stress, and amino acids, to regulate cell growth and proliferation, protein synthesis, protein degradation, and other physiological and biochemical processes. The mTOR-Rheb-TSC-TBC complex co-localizes to the lysosome and the phosphorylation of TSC-TBC effects the dissociation of the complex from the lysosome and activates Rheb. GTP-bound Rheb potentiates the catalytic activity of mTORC1. Under conditions with growth factors and amino acids, v-ATPase, Ragulator, Rag GTPase, Rheb, hVps34, PLD1, and PA have important but disparate effects on mTORC1 activation. In this review, we introduce five models of mTORC1 activation by growth factors and amino acids to provide a comprehensive theoretical foundation for future research.
Collapse
Affiliation(s)
- Xu Zheng
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Yan Liang
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Qiburi He
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Ruiyuan Yao
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Wenlei Bao
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Lili Bao
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Yanfeng Wang
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Zhigang Wang
- College of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| |
Collapse
|
43
|
Park SJ, Ryu J, Kim IH, Choi YH, Nam TJ. Activation of the mTOR signaling pathway in breast cancer MCF‑7 cells by a peptide derived from Porphyra yezoensis. Oncol Rep 2014; 33:19-24. [PMID: 25333576 PMCID: PMC4254673 DOI: 10.3892/or.2014.3557] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 09/26/2014] [Indexed: 11/15/2022] Open
Abstract
Seaweeds have beneficial nutritional and medicinal properties. Several studies have examined the polysaccharides found in the extracts of Porphyra yezoensis (PPY), although the effects of particular proteins have not been reported, and peptides from the marine alga PPY function in antitumor cell signaling, although the precise mechanism is not well understood. Apoptosis plays an important role in cell death, which affects cell proliferation. Generally, regulation of apoptosis requires participation of the p53 and Bcl-2 family by the mammalian target of rapamycin (mTOR) pathway, which is activated in a variety of malignant cancers. Autophagy is another signaling pathway that leads to degradation of cellular components by lysosomal activity, and the relationship between autophagy and cancer has been of interest for several years. The present study investigated mTOR pathway activation in MCF-7 cells treated with 500 ng PPY for 24 h by assessing LC3 as a monitor of autophagy. We observed that the p53/NF-κB and mTOR pathways were affected by PPY, which contributes to our understanding of the functional relationship between the Bcl-2 family and mTOR under apoptotic conditions in MCF-7 cells.
Collapse
Affiliation(s)
- Su-Jin Park
- Department of Food and Science, Pukyong National University, Busan 608-737, Republic of Korea
| | - Jina Ryu
- Department of Food and Science, Pukyong National University, Busan 608-737, Republic of Korea
| | - In-Hye Kim
- Institute of Fisheries Science, Pukyong National University, Busan 619-911, Republic of Korea
| | - Youn-Hee Choi
- Institute of Fisheries Science, Pukyong National University, Busan 619-911, Republic of Korea
| | - Taek-Jeong Nam
- Department of Food and Science, Pukyong National University, Busan 608-737, Republic of Korea
| |
Collapse
|
44
|
Schwabe A, Bruggeman FJ. Single yeast cells vary in transcription activity not in delay time after a metabolic shift. Nat Commun 2014; 5:4798. [DOI: 10.1038/ncomms5798] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 07/25/2014] [Indexed: 11/09/2022] Open
|
45
|
|
46
|
West nile virus-induced activation of mammalian target of rapamycin complex 1 supports viral growth and viral protein expression. J Virol 2014; 88:9458-71. [PMID: 24920798 DOI: 10.1128/jvi.01323-14] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Since its introduction in New York City, NY, in 1999, West Nile virus (WNV) has spread to all 48 contiguous states of the United States and is now the leading cause of epidemic encephalitis in North America. As a member of the family Flaviviridae, WNV is part of a group of clinically important human pathogens, including dengue virus and Japanese encephalitis virus. The members of this family of positive-sense, single-stranded RNA viruses have limited coding capacity and are therefore obligated to co-opt a significant amount of cellular factors to translate their genomes effectively. Our previous work has shown that WNV growth was independent of macroautophagy activation, but the role of the evolutionarily conserved mammalian target of rapamycin (mTOR) pathway during WNV infection was not well understood. mTOR is a serine/threonine kinase that acts as a central cellular censor of nutrient status and exercises control of vital anabolic and catabolic cellular responses such as protein synthesis and autophagy, respectively. We now show that WNV activates mTOR and cognate downstream activators of cap-dependent protein synthesis at early time points postinfection and that pharmacologic inhibition of mTOR (KU0063794) significantly reduced WNV growth. We used an inducible Raptor and Rictor knockout mouse embryonic fibroblast (MEF) system to further define the role of mTOR complexes 1 and 2 in WNV growth and viral protein synthesis. Following inducible genetic knockout of the major mTOR cofactors raptor (TOR complex 1 [TORC1]) and rictor (TORC2), we now show that TORC1 supports flavivirus protein synthesis via cap-dependent protein synthesis pathways and supports subsequent WNV growth. IMPORTANCE Since its introduction in New York City, NY, in 1999, West Nile virus (WNV) has spread to all 48 contiguous states in the United States and is now the leading cause of epidemic encephalitis in North America. Currently, the mechanism by which flaviviruses such as WNV translate their genomes in host cells is incompletely understood. Elucidation of the host mechanisms required to support WNV genome translation will provide broad understanding for the basic mechanisms required to translate capped viral RNAs. We now show that WNV activates mTOR and cognate downstream activators of cap-dependent protein synthesis at early time points postinfection. Following inducible genetic knockout of the major mTOR complex cofactors raptor (TORC1) and rictor (TORC2), we now show that TORC1 supports WNV growth and protein synthesis. This study demonstrates the requirement for TORC1 function in support of WNV RNA translation and provides insight into the mechanisms underlying flaviviral RNA translation in mammalian cells.
Collapse
|
47
|
Rehman G, Shehzad A, Khan AL, Hamayun M. Role of AMP-activated protein kinase in cancer therapy. Arch Pharm (Weinheim) 2014; 347:457-68. [PMID: 24677093 DOI: 10.1002/ardp.201300402] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/23/2014] [Accepted: 01/31/2014] [Indexed: 11/07/2022]
Abstract
Recent advances in AMP-activated protein kinase (AMPK) as a target in cancer waxed and waned over the past decade of cancer research. AMPK is a cellular energy sensor, present in almost all eukaryotic cells. An elevated AMP/ATP ratio activates the AMPK, which in turn inhibits energy-consuming processes and induces catabolic events that generate ATP to restore the energy homeostasis inside the cell. Several reports have indicated that AMPK regulates several metabolic pathways and may be a potential therapeutic target for the treatment of cancer. Cancer cells have specific metabolic changes that differ from normal cells, and AMPK prevents the deregulated processes in cancer. AMPK may also act to inhibit tumor formation through modulation of cell growth, cell proliferation, autophagy, stress responses, and cell polarity. AMPK has been shown to inhibit mammalian target of rapamycin (mTOR) through tuberous sclerosis complex 2 (TSC2) phosphorylation and phosphatase and tensin homolog (PTEN), considered as central cell growth controller signals in diseases. In response to glucose deprivation, AMPK phosphorylates and activates p53, which induces cell cycle arrest in the G1/S phase of the cell cycle. AMPK has also been reported to block cyclin-dependent kinases through phosphorylation of p27(kip1) , promoting its stabilization and allowing cells to survive metabolic stress via induction of autophagy. Additionally, AMPK induces autophagy by phosphorylation and activation of eEF-2 kinase, and prevents the formation of new proteins. AMPK activators are also used for the treatment of type II diabetes and cancer. This review focuses on AMPK activation and its possible therapeutic role in the treatment of cancer.
Collapse
Affiliation(s)
- Gauhar Rehman
- School of Life Science, College of Natural Science, Kyungpook National University, Daegu, South Korea; Department of Zoology, Abdul Wali Khan University, Mardan, K. P. K. Pakistan
| | | | | | | |
Collapse
|
48
|
Suryawan A, Nguyen HV, Almonaci RD, Davis TA. Differential regulation of protein synthesis in skeletal muscle and liver of neonatal pigs by leucine through an mTORC1-dependent pathway. J Anim Sci Biotechnol 2014; 3. [PMID: 22675606 PMCID: PMC3366465 DOI: 10.1186/2049-1891-3-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Neonatal growth is characterized by a high protein synthesis rate that is largely due to an enhanced sensitivity to the postprandial rise in insulin and amino acids, especially leucine. The mechanism of leucine's action in vivo is not well understood. In this study, we investigated the effect of leucine infusion on protein synthesis in skeletal muscle and liver of neonatal pigs. To evaluate the mode of action of leucine, we used rapamycin, an inhibitor of mammalian target of rapamycin (mTOR) complex-1 (mTORC1). Overnight-fasted 7-day-old piglets were treated with rapamycin for 1 hour and then infused with leucine (400 μmol·kg(-1)·h(-1)) for 1 hour. Leucine infusion increased the rate of protein synthesis, and ribosomal protein S6 kinase 1 (S6K1) and eukaryotic initiation factor (eIF) 4E-binding protein-1 (4E-BP1) phosphorylation in gastrocnemius and masseter muscles (P < 0.05), but not in the liver. The leucine-induced stimulation of protein synthesis and S6K1 and 4E-BP1 phosphorylation were completely blocked by rapamycin, suggesting that leucine action is by an mTORC1-dependent mechanism. Neither leucine nor rapamycin had any effect on the activation of the upstream mTORC1 regulators, AMP-activated protein kinase and protein kinase B, in skeletal muscle or liver. The activation of eIF2α and elongation factor 2 was not affected by leucine or rapamycin, indicating that these two pathways are not limiting steps of leucine-induced protein synthesis. These results suggest that leucine stimulates muscle protein synthesis in neonatal pigs by inducing the activation of mTORC1 and its downstream pathway leading to mRNA translation.
Collapse
Affiliation(s)
- Agus Suryawan
- Department of Pediatrics, Baylor College of Medicine, United States, Department of Agriculture/Agriculture Research Service Children's Nutrition Research Center, 1100 Bates Street, Houston, TX 77030, USA
| | | | | | | |
Collapse
|
49
|
Teixeira V, Medeiros TC, Vilaça R, Moradas-Ferreira P, Costa V. Reduced TORC1 signaling abolishes mitochondrial dysfunctions and shortened chronological lifespan of Isc1p-deficient cells. MICROBIAL CELL 2014; 1:21-36. [PMID: 28357207 PMCID: PMC5349163 DOI: 10.15698/mic2014.01.121] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The target of rapamycin (TOR) is an important signaling pathway on a hierarchical
network of interacting pathways regulating central biological processes, such as
cell growth, stress response and aging. Several lines of evidence suggest a
functional link between TOR signaling and sphingolipid metabolism. Here, we
report that the TORC1-Sch9p pathway is activated in cells lacking Isc1p, the
yeast orthologue of mammalian neutral sphingomyelinase 2. The deletion of
TOR1 or SCH9 abolishes the premature
aging, oxidative stress sensitivity and mitochondrial dysfunctions displayed by
isc1Δ cells and this is correlated with the suppression of
the autophagic flux defect exhibited by the mutant strain. The protective effect
of TOR1 deletion, as opposed to that of SCH9
deletion, is not associated with the attenuation of Hog1p hyperphosphorylation,
which was previously implicated in isc1Δ phenotypes. Our data
support a model in which Isc1p regulates mitochondrial function and
chronological lifespan in yeast through the TORC1-Sch9p pathway although Isc1p
and TORC1 also seem to act through independent pathways, as
isc1Δtor1Δ phenotypes are intermediate to
those displayed by isc1Δ and tor1Δ cells. We
also provide evidence that TORC1 downstream effectors, the type 2A protein
phosphatase Sit4p and the AGC protein kinase Sch9p, integrate nutrient and
stress signals from TORC1 with ceramide signaling derived from Isc1p to regulate
mitochondrial function and lifespan in yeast. Overall, our results show that
TORC1-Sch9p axis is deregulated in Isc1p-deficient cells, contributing to
mitochondrial dysfunction, enhanced oxidative stress sensitivity and premature
aging of isc1Δ cells.
Collapse
Affiliation(s)
- Vitor Teixeira
- Instituto de Biologia Molecular e Celular, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal. ; Departamento de Biologia Molecular, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Tânia C Medeiros
- Instituto de Biologia Molecular e Celular, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal
| | - Rita Vilaça
- Instituto de Biologia Molecular e Celular, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal. ; Departamento de Biologia Molecular, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Pedro Moradas-Ferreira
- Instituto de Biologia Molecular e Celular, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal. ; Departamento de Biologia Molecular, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Vítor Costa
- Instituto de Biologia Molecular e Celular, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal. ; Departamento de Biologia Molecular, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| |
Collapse
|
50
|
Gancz D, Gilboa L. Insulin and Target of rapamycin signaling orchestrate the development of ovarian niche-stem cell units in Drosophila. Development 2013; 140:4145-54. [PMID: 24026119 DOI: 10.1242/dev.093773] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Tissue-specific stem cells and their niches are organized into functional units that respond to external cues in order to maintain organ homeostasis. Insulin and Target of rapamycin (Tor) signaling mediate external cues that control adult niches and stem cells. Whether these pathways play a role in the establishment of niche-stem cell units during organogenesis has been little explored. We show that during larval development both Insulin-like receptor (InR) and Tor participate in the establishment of ovarian niches and germline stem cells (GSCs) in Drosophila melanogaster. Tor and InR are required cell-autonomously for the proliferation of precursors for both somatic niches and GSCs. These pathways also promote the formation of terminal filaments (part of the somatic niche). Significantly, InR, but not Tor, signaling non-autonomously promotes primordial germ cell (PGC) differentiation. Somatic attenuation of the pathway retards PGC differentiation, whereas its activation results in their precocious differentiation. We also show that InR-mediated PGC differentiation is independent of somatic ecdysone signaling, but that further differentiation into cysts requires an ecdysone input. These results demonstrate that Tor and InR signaling actively participate in the formation of ovarian niches and stem cells by affecting both cell numbers and differentiation. The dual influence of Tor and InR on both somatic cells and PGCs ensures that these two cell populations develop coordinately. Our work further identifies a novel step in the regulation of germ cell differentiation by demonstrating that following bag of marbles expression, cyst formation requires an additional hormonal input.
Collapse
Affiliation(s)
- Dana Gancz
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
| | | |
Collapse
|