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Dual Roles of Serine-Threonine Kinase Receptor-Associated Protein (STRAP) in Redox-Sensitive Signaling Pathways Related to Cancer Development. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:5241524. [PMID: 29849900 PMCID: PMC5933018 DOI: 10.1155/2018/5241524] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Accepted: 03/08/2018] [Indexed: 02/07/2023]
Abstract
Serine-threonine kinase receptor-associated protein (STRAP) is a transforming growth factor β (TGF-β) receptor-interacting protein that has been implicated in both cell proliferation and cell death in response to various stresses. However, the precise roles of STRAP in these cellular processes are still unclear. The mechanisms by which STRAP controls both cell proliferation and cell death are now beginning to be unraveled. In addition to its biological roles, this review also focuses on the dual functions of STRAP in cancers displaying redox dysregulation, where it can behave as a tumor suppressor or an oncogene (i.e., it can either inhibit or promote tumor formation), depending on the cellular context. Further studies are needed to define the functions of STRAP and the redox-sensitive intracellular signaling pathways that enhance either cell proliferation or cell death in human cancer tissues, which may help in the development of effective treatments for cancer.
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Bi X, Zhang G, Wang X, Nguyen C, May HI, Li X, Al-Hashimi AA, Austin RC, Gillette TG, Fu G, Wang ZV, Hill JA. Endoplasmic Reticulum Chaperone GRP78 Protects Heart From Ischemia/Reperfusion Injury Through Akt Activation. Circ Res 2018; 122:1545-1554. [PMID: 29669712 DOI: 10.1161/circresaha.117.312641] [Citation(s) in RCA: 118] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 03/30/2018] [Accepted: 04/17/2018] [Indexed: 12/14/2022]
Abstract
RATIONALE Restoration of coronary artery blood flow is the most effective means of ameliorating myocardial damage triggered by ischemic heart disease. However, coronary reperfusion elicits an increment of additional injury to the myocardium. Accumulating evidence indicates that the unfolded protein response (UPR) in cardiomyocytes is activated by ischemia/reperfusion (I/R) injury. Xbp1s (spliced X-box binding protein 1), the most highly conserved branch of the unfolded protein response, is protective in response to cardiac I/R injury. GRP78 (78 kDa glucose-regulated protein), a master regulator of the UPR and an Xbp1s target, is upregulated after I/R. However, its role in the protective response of Xbp1s during I/R remains largely undefined. OBJECTIVE To elucidate the role of GRP78 in the cardiomyocyte response to I/R using both in vitro and in vivo approaches. METHODS AND RESULTS Simulated I/R injury to cultured neonatal rat ventricular myocytes induced apoptotic cell death and strong activation of the UPR and GRP78. Overexpression of GRP78 in neonatal rat ventricular myocytes significantly protected myocytes from I/R-induced cell death. Furthermore, cardiomyocyte-specific overexpression of GRP78 ameliorated I/R damage to the heart in vivo. Exploration of underlying mechanisms revealed that GRP78 mitigates cellular damage by suppressing the accumulation of reactive oxygen species. We go on to show that the GRP78-mediated cytoprotective response involves plasma membrane translocation of GRP78 and interaction with PI3 kinase, culminating in stimulation of Akt. This response is required as inhibition of the Akt pathway significantly blunted the antioxidant activity and cardioprotective effects of GRP78. CONCLUSIONS I/R induction of GRP78 in cardiomyocytes stimulates Akt signaling and protects against oxidative stress, which together protect cells from I/R damage.
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Affiliation(s)
- Xukun Bi
- From the Department of Cardiology, Biomedical Research (Therapy) Center, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China (X.B., X.L., G.F.).,Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.)
| | - Guangyu Zhang
- Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.).,University of Texas Southwestern Medical Center, Dallas; Department of Cardiology, Zhongnan Hospital of Wuhan University, Hubei, China (G.Z.)
| | - Xiaoding Wang
- Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.).,Department of Cardiology, Renmin Hospital of Wuhan University, Hubei, China (X.W.)
| | - Chau Nguyen
- Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.)
| | - Herman I May
- Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.)
| | - Xiaoting Li
- From the Department of Cardiology, Biomedical Research (Therapy) Center, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China (X.B., X.L., G.F.)
| | - Ali A Al-Hashimi
- Department of Medicine, Hamilton Center for Kidney Research, McMaster University and the Research Institute of St. Joseph's Healthcare Hamilton, ON, Canada (A.A.A.-H., R.C.A.)
| | - Richard C Austin
- Department of Medicine, Hamilton Center for Kidney Research, McMaster University and the Research Institute of St. Joseph's Healthcare Hamilton, ON, Canada (A.A.A.-H., R.C.A.)
| | - Thomas G Gillette
- Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.)
| | - Guosheng Fu
- From the Department of Cardiology, Biomedical Research (Therapy) Center, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China (X.B., X.L., G.F.)
| | - Zhao V Wang
- Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.)
| | - Joseph A Hill
- Division of Cardiology, Department of Internal Medicine (X.B., G.Z., X.W., C.N., H.I.M., T.G.G., Z.V.W., J.A.H.).,Department of Molecular Biology (J.A.H.)
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Anticancer Properties of Essential Oils and Other Natural Products. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2018; 2018:3149362. [PMID: 29765461 PMCID: PMC5889900 DOI: 10.1155/2018/3149362] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 02/13/2018] [Indexed: 02/06/2023]
Abstract
Essential oils are secondary metabolites with a key-role in plants protection, consisting primarily of terpenes with a volatile nature and a diverse array of chemical structures. Essential oils exhibit a wide range of bioactivities, especially antimicrobial activity, and have long been utilized for treating various human ailments and diseases. Cancer cell prevention and cytotoxicity are exhibited through a wide range of mechanisms of action, with more recent research focusing on synergistic and antagonistic activity between specific essential oils major and minor components. Essential oils have been shown to possess cancer cell targeting activity and are able to increase the efficacy of commonly used chemotherapy drugs including paclitaxel and docetaxel, having also shown proimmune functions when administered to the cancer patient. The present review represents a state-of-the-art review of the research behind the application of EOs as anticancer agents both in vitro and in vivo. Cancer cell target specificity and the use of EOs in combination with conventional chemotherapeutic strategies are also explored.
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Dawar FU, Hu X, Zhao L, Dong X, Xiong Y, Zhou M, Liang R, Sarath Babu V, Li J, Mei J, Lin L. Transcriptomic analysis reveals differentially expressed genes and a unique apoptosis pathway in channel catfish ovary cells after infection with the channel catfish virus. FISH & SHELLFISH IMMUNOLOGY 2017; 71:58-68. [PMID: 28970047 DOI: 10.1016/j.fsi.2017.09.070] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/16/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
The channel catfish virus (CCV) can cause lethal hemorrhagic infection in juvenile channel catfish, thereby resulting in a huge economic loss to the fish industry. The genome of the CCV has been fully sequenced, and its prevalence is well documented. However, less is known about the molecular mechanisms and pathogenesis of the CCV. Herein, the channel catfish ovary cells (CCO) were infected with CCV and their transcriptomic sketches were analyzed using an RNA sequencing technique. In total, 72,686,438 clean reads were obtained from 73,231,128 sequence reads, which were further grouped into 747,168 contigs. These contigs were assembled into 49,119 unigenes, of which 20,912 and 18,333 unigenes were found in Nr and SwissProt databases and matched 15,911 and 14,625 distinctive proteins, respectively. From these, 3641 differentially expressed genes (DEGs), comprising 260 up-regulated and 3381 down-regulated genes, were found compared with the control (non-infected) cells. For verification, 16 DEGs were analyzed using qRT-PCR. The analysis of the DEGs and their related cellular signaling pathways revealed a substantial number of DEGs that were involved in the apoptosis pathway induced by CCV infection. The apoptosis pathways were further elucidated using standard apoptosis assays. The results showed that CCV could induce extrinsic apoptosis pathway (instead of a mitochondrial intrinsic apoptosis pathway) in CCO cells. This study helps our understanding of the pathogenesis of CCV and contributes to the prevention of CCV infection in channel catfish.
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Affiliation(s)
- Farman Ullah Dawar
- Department of Aquatic Animal Medicine, College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China; Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, 510225, China
| | - Xianqin Hu
- Department of Aquatic Animal Medicine, College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China; School of Animal Sciences and Nutritional Engineering, Wuhan Polytechnic University, Wuhan, Hubei, 430023, China
| | - Lijuan Zhao
- Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, 510225, China
| | - Xingxing Dong
- Department of Aquatic Animal Medicine, College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Yang Xiong
- Department of Aquatic Animal Medicine, College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Meng Zhou
- Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, 510225, China
| | - Rishen Liang
- Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, 510225, China
| | - V Sarath Babu
- Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, 510225, China
| | - Jun Li
- School of Biological Sciences, Lake Superior State University, Sault Ste. Marie, MI 49783, USA; Laboratory for Marine Fisheries Science and Food Production Processes, National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266071, China
| | - Jie Mei
- Department of Aquatic Animal Medicine, College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
| | - Li Lin
- Department of Aquatic Animal Medicine, College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China; Guangzhou Key Laboratory of Aquatic Animal Diseases and Waterfowl Breeding, Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding, College of Animal Sciences and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, 510225, China; Laboratory for Marine Fisheries Science and Food Production Processes, National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266071, China; Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, 510640, China.
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55
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Zhao C, Xu Z, Wang Z, Suo C, Tao J, Han Z, Gu M, Tan R. Role of tumor necrosis factor-α in epithelial-to-mesenchymal transition in transplanted kidney cells in recipients with chronic allograft dysfunction. Gene 2017; 642:483-490. [PMID: 29174387 DOI: 10.1016/j.gene.2017.11.059] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 11/16/2017] [Accepted: 11/21/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND Chronic allograft dysfunction (CAD) is characterized by allograft kidney interstitial fibrosis, the underlying mechanism of which is unclear. Our aim was to elucidate the role and mechanism of TNF-α-induced epithelial-to-mesenchymal transition (EMT) in transplant kidney tubular interstitial fibrosis. METHODS Human kidney tissues from normal volunteers and CAD patients were assessed using periodic acid-Schiff, Masson trichrome and immunohistochemical staining. mRNA and protein expression of E-cadherin, α-smooth muscle actin (SMA) and fibronectin(FN) in renal proximal tubule epithelial (HK-2) cells after treatment with TNF-α under different conditions were assessed using western blot and qRT-PCR analysis. Cell motility and migration were assessed using wound healing and transwell assays. Expression of Smurf2 and TNF-α-signaling pathway-related proteins in HK-2 cells treated with TNF-α was detected by western blotting. E-cadherin and α-SMA expression was also assessed in Smurf2 plasmid-transfected or Smurf2 siRNA-treated HK-2 cells. RESULTS The expression of TNF-α, Smurf2, α-SMA, and fibronectin was significantly upregulated, while the expression of E-cad was downregulated in the CAD group compared with the normal group. The in vitro results showed that TNF-α remarkably upregulated the expression of Smurf2, α-SMA and fibronectin and downregulated the expression of E-cadherin in HK-2 cells and enhanced motility and migration in HK-2 cells. Overexpression of Smurf2 could promote the expression of α-SMA and inhibit the expression of E-cad, whereas knockdown of Smurf2 expression reversed TNF-α-induced upregulation of α-SMA and prohibited the reduction of E-cad expression. Furthermore, TNF-α-induced Smurf2 expression promoted EMT through the Akt signaling pathway. CONCLUSIONS TNF-α induced EMT via the TNF-α/Akt/Smurf2 signaling pathways, and it may play a role in aggravating allograft kidney interstitial fibrosis in CAD patients.
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Affiliation(s)
- Chunchun Zhao
- Department of Urology, Nanjing Medical University First Affiliated Hospital, Nanjing 210029, China
| | - Zhen Xu
- Department of Urology, Taizhou First People's Hospital, Taizhou 225300, China
| | - Zijie Wang
- Department of Urology, Nanjing Medical University First Affiliated Hospital, Nanjing 210029, China
| | - Chuanjian Suo
- Department of Urology, Nanjing Medical University First Affiliated Hospital, Nanjing 210029, China
| | - Jun Tao
- Department of Urology, Nanjing Medical University First Affiliated Hospital, Nanjing 210029, China
| | - Zhijian Han
- Department of Urology, Nanjing Medical University First Affiliated Hospital, Nanjing 210029, China
| | - Min Gu
- Department of Urology, Nanjing Medical University First Affiliated Hospital, Nanjing 210029, China.
| | - Ruoyun Tan
- Department of Urology, Nanjing Medical University First Affiliated Hospital, Nanjing 210029, China.
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Qian H, Chen S, Pan Y, Chen J. Understanding the relative affinity and specificity of the substrate binding site of protein kinase B for substrate-mimetic inhibitors. MOLECULAR SIMULATION 2017. [DOI: 10.1080/08927022.2017.1319062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Haiyan Qian
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, P.R. China
| | - Shifeng Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, P.R. China
| | - Youlu Pan
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, P.R. China
| | - Jianzhong Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, P.R. China
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57
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Bolten CW, Blanner PM, McDonald WG, Staten NR, Mazzarella RA, Arhancet GB, Meier MF, Weiss DJ, Sullivan PM, Hromockyj AE, Kletzien RF, Colca JR. Insulin Sensitizing Pharmacology of Thiazolidinediones Correlates with Mitochondrial Gene Expression rather than Activation of PPARγ. GENE REGULATION AND SYSTEMS BIOLOGY 2017. [DOI: 10.1177/117762500700100008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Insulin sensitizing thiazolidinediones (TZDs) are generally considered to work as agonists for the nuclear receptor peroxisome proliferative activated receptor-gamma (PPARγ). However, TZDs also have acute, non-genomic metabolic effects and it is unclear which actions are responsible for the beneficial pharmacology of these compounds. We have taken advantage of an analog, based on the metabolism of pioglitazone, which has much reduced ability to activate PPARγ. This analog (PNU-91325) was compared to rosiglitazone, the most potent PPARγ activator approved for human use, in a variety of studies both in vitro and in vivo. The data demonstrate that PNU-91325 is indeed much less effective than rosiglitazone at activating PPARγ both in vitro and in vivo. In contrast, both compounds bound similarly to a mitochondrial binding site and acutely activated PI-3 kinase-directed phosphorylation of AKT, an action that was not affected by elimination of PPARγ activation. The two compounds were then compared in vivo in both normal C57 mice and diabetic KKAy mice to determine whether their pharmacology correlated with biomarkers of PPARγ activation or with the expression of other gene transcripts. As expected from previous studies, both compounds improved insulin sensitivity in the diabetic mice, and this occurred in spite of the fact that there was little increase in expression of the classic PPARγ target biomarker adipocyte binding protein-2 (aP2) with PNU-91325 under these conditions. An examination of transcriptional profiling of key target tissues from mice treated for one week with both compounds demonstrated that the relative pharmacology of the two thiazolidinediones correlated best with an increased expression of an array of mitochondrial proteins and with expression of PPARγ coactivator 1-alpha (PGC1α), the master regulator of mitochondrial biogenesis. Thus, important pharmacology of the insulin sensitizing TZDs may involve acute actions, perhaps on the mitochondria, that are independent of direct activation of the nuclear receptor PPARγ. These findings suggest a potential alternative route to the discovery of novel insulin sensitizing drugs.
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Affiliation(s)
- Charles W. Bolten
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Patrick M. Blanner
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - William G. McDonald
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Nicholas R. Staten
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Richard A. Mazzarella
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Graciela B. Arhancet
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Martin F. Meier
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - David J. Weiss
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Patrick M. Sullivan
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Alexander E. Hromockyj
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Rolf F. Kletzien
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
| | - Jerry R. Colca
- Discovery Research, Pfizer Corporation 700 Chesterfield Parkway West Chesterfield, MO 63017
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Metabolic syndrome in rats is associated with erectile dysfunction by impairing PI3K/Akt/eNOS activity. Sci Rep 2017; 7:13464. [PMID: 29044143 PMCID: PMC5647376 DOI: 10.1038/s41598-017-12907-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 09/12/2017] [Indexed: 12/04/2022] Open
Abstract
Metabolic syndrome (MetS) is a risk factor for erectile dysfunction (ED), but the underlying mechanisms are unclear. The aims of this study were to determine the underlying mechanisms of metabolic syndrome-related ED (MED). Sprague Dawley (SD) rats were fed a high-fat diet for 6 months, and metabolic parameters were then assessed. An apomorphine test was conducted to confirm MED. Only rats with MED were administered an intracavernosal injection of either epidermal growth factor (EGF) or vehicle for 4 weeks. Erectile responses were evaluated by determining the mean arterial blood pressure (MAP) and intracavernosal pressure (ICP). Levels of protein expression were examined by western blotting and immunohistochemistry. Body weight, fasting blood glucose, plasma insulin and plasma total cholesterol were increased in the MetS rats compared with those in control rats (each p < 0.05). The maximum ICP/MAP, total ICP/MAP and concentration of cyclic guanosine mono-phosphate (cGMP) were significantly decreased in MED rats (each p < 0.05). The expression levels of p110α, p-Akt1 (Tyr308)/Akt1 and p-eNOS (Ser1177)/eNOS were reduced in MED rats (each p < 0.05). Activation of the PI3K/Akt/eNOS signaling cascade (intracavernosal injection of EGF) reversed these changes (each p < 0.05). The present study demonstrates that downregulation of the PI3K/Akt/eNOS signaling pathway is involved in MED.
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Oyagbemi AA, Omobowale TO, Asenuga ER, Afolabi JM, Adejumobi OA, Adedapo AA, Yakubu MA. Effect of arsenic acid withdrawal on hepatotoxicity and disruption of erythrocyte antioxidant defense system. Toxicol Rep 2017; 4:521-529. [PMID: 29657918 PMCID: PMC5897320 DOI: 10.1016/j.toxrep.2017.09.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 09/21/2017] [Accepted: 09/26/2017] [Indexed: 01/19/2023] Open
Abstract
We investigated the effects of withdrawal from Sodium arsenite (NaAsO2) on the hepatic and antioxidant defense system in male Wistar rats using a before and after toxicant design. Rats were orally gavaged daily with varying doses of NaAsO2 for a period of 4 weeks. One half of the population was sacrificed and the remaining half had the toxicant withdrawn for another further 4 weeks. Biochemical and immunohistochemical techniques were used to assess the impact of withdrawal on the erythrocyte and hepatic systems. Exposure of Wistar rats to NaASO2 led to a significant (p < 0.05) increase in hepatic and erythrocyte markers of oxidative stress (malondialdehyde, thiol contents and hydrogen peroxide generation). Concurrently, there was a significant (p < 0.05) increase in hepatic and erythrocyte antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and superoxide dismutase) following exposure. Withdrawal from NaAsO2 exposure led to a decline in both erythrocyte and hepatic markers of oxidative stress and together with a significant improvement in antioxidant defense system. Histopathology and immunohistochemistry revealed varying degrees of recovery in hepatocyte ultrastructure alongside increased expression of the pro-survival protein Kinase B (Akt/PKB) after 4 weeks of NaAsO2 withdrawal. Conclusively, withdrawal from exposure led to a partial recovery from oxidative stress-mediated hepatotoxicity and derangements in erythrocyte antioxidant system through Akt/PKB pathway.
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Affiliation(s)
- A A Oyagbemi
- Department of Veterinary Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
| | - T O Omobowale
- Department of Veterinary Medicine, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
| | - E R Asenuga
- Department of Veterinary Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Benin, Nigeria
| | - J M Afolabi
- Department of Veterinary Medicine, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
| | - O A Adejumobi
- Department of Veterinary Medicine, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
| | - A A Adedapo
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
| | - M A Yakubu
- Department of Environmental and Interdisciplinary Sciences, College of Science, Technology and Engineering, Texas Southern University, 3100 Cleburne Avenue, Houston, TX 77004, USA
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Nakayama M, Ohara N. Molecular mechanisms of Porphyromonas gingivalis-host cell interaction on periodontal diseases. JAPANESE DENTAL SCIENCE REVIEW 2017; 53:134-140. [PMID: 29201258 PMCID: PMC5703693 DOI: 10.1016/j.jdsr.2017.06.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 02/03/2017] [Accepted: 06/28/2017] [Indexed: 12/31/2022] Open
Abstract
Porphyromonas gingivalis (P. gingivalis) is a major oral pathogen and associated with periodontal diseases including periodontitis and alveolar bone loss. In this review, we indicate that two virulence factors, which are hemoglobin receptor protein (HbR) and cysteine proteases “gingipains”, expressed by P. gingivalis have novel functions on the pathogenicity of P. gingivalis. P. gingivalis produces three types of gingipains and concomitantly several adhesin domains. Among the adhesin domains, hemoglobin receptor protein (HbR), also called HGP15, has the function of induction of interleukin-8 (IL-8) expression in human gingival epithelial cells, indicating the possibility that HbR is associated with P. gingivalis-induced periodontal inflammation. On bacteria-host cells contact, P. gingivalis induces cellular signaling alteration in host cells. Phosphatidylinositol 3-kinase (PI3K) and Akt are well known to play a pivotal role in various cellular physiological functions including cell survival and glucose metabolism in mammalian cells. Recently, we demonstrated that gingipains attenuate the activity of PI3K and Akt, which might have a causal influence on periodontal diseases by chronic infection to the host cells from the speculation of molecular analysis. In this review, we discuss new molecular and biological characterization of the virulence factors from P. gingivalis.
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Affiliation(s)
- Masaaki Nakayama
- Department of Oral Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan.,The Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University, Okayama 700-8558, Japan
| | - Naoya Ohara
- Department of Oral Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan.,The Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University, Okayama 700-8558, Japan
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Nakayama M, Ohara N. Novel function of Porphyromonas gingivalis gingipains in the PI3K/Akt signaling pathway. J Oral Biosci 2017. [DOI: 10.1016/j.job.2017.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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De Marco C, Laudanna C, Rinaldo N, Oliveira DM, Ravo M, Weisz A, Ceccarelli M, Caira E, Rizzuto A, Zoppoli P, Malanga D, Viglietto G. Specific gene expression signatures induced by the multiple oncogenic alterations that occur within the PTEN/PI3K/AKT pathway in lung cancer. PLoS One 2017; 12:e0178865. [PMID: 28662101 PMCID: PMC5491004 DOI: 10.1371/journal.pone.0178865] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 05/19/2017] [Indexed: 01/04/2023] Open
Abstract
Hyperactivation of the phosphatydil-inositol-3' phosphate kinase (PI3K)/AKT pathway is observed in most NSCLCs, promoting proliferation, migration, invasion and resistance to therapy. AKT can be activated through several mechanisms that include loss of the negative regulator PTEN, activating mutations of the catalytic subunit of PI3K (PIK3CA) and/or mutations of AKT1 itself. However, number and identity of downstream targets of activated PI3K/AKT pathway are poorly defined. To identify the genes that are targets of constitutive PI3K/AKT signalling in lung cancer cells, we performed a comparative transcriptomic analysis of human lung epithelial cells (BEAS-2B) expressing active mutant AKT1 (AKT1-E17K), active mutant PIK3CA (PIK3CA-E545K) or that are silenced for PTEN. We found that, altogether, aberrant PI3K/AKT signalling in lung epithelial cells regulated the expression of 1,960/20,436 genes (9%), though only 30 differentially expressed genes (DEGs) (15 up-regulated, 12 down-regulated and 3 discordant) out of 20,436 that were common among BEAS-AKT1-E17K, BEAS-PIK3CA-E545K and BEAS-shPTEN cells (0.1%). Conversely, DEGs specific for mutant AKT1 were 133 (85 up-regulated; 48 down-regulated), DEGs specific for mutant PIK3CA were 502 (280 up-regulated; 222 down-regulated) and DEGs specific for PTEN loss were 1549 (799 up-regulated, 750 down-regulated). The results obtained from array analysis were confirmed by quantitative RT-PCR on selected up- and down-regulated genes (n = 10). Treatment of BEAS-C cells and the corresponding derivatives with pharmacological inhibitors of AKT (MK2206) or PI3K (LY294002) further validated the significance of our findings. Moreover, mRNA expression of selected DEGs (SGK1, IGFBP3, PEG10, GDF15, PTGES, S100P, respectively) correlated with the activation status of the PI3K/AKT pathway assessed by S473 phosphorylation in NSCLC cell lines (n = 6). Finally, we made use of Ingenuity Pathway Analysis (IPA) to investigate the relevant BioFunctions enriched by the costitutive activation of AKT1-, PI3K- or PTEN-dependent signalling in lung epithelial cells. Expectedly, the analysis of the DEGs common to all three alterations highlighted a group of BioFunctions that included Cell Proliferation of tumor cell lines (14 DEGs), Invasion of cells (10 DEGs) and Migration of tumour cell lines (10 DEGs), with a common core of 5 genes (ATF3, CDKN1A, GDF15, HBEGF and LCN2) that likely represent downstream effectors of the pro-oncogenic activities of PI3K/AKT signalling. Conversely, IPA analysis of exclusive DEGs led to the identification of different downstream effectors that are modulated by mutant AKT1 (TGFBR2, CTSZ, EMP1), mutant PIK3CA (CCND2, CDK2, IGFBP2, TRIB1) and PTEN loss (ASNS, FHL2). These findings not only shed light on the molecular mechanisms that are activated by aberrant signalling through the PI3K/AKT pathway in lung epithelial cells, but also contribute to the identification of previously unrecognised molecules whose regulation takes part in the development of lung cancer.
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Affiliation(s)
- Carmela De Marco
- Dipartimento di Medicina Sperimentale e Clinica, Università "Magna Graecia", Catanzaro, Italia
| | - Carmelo Laudanna
- Dipartimento di Medicina Sperimentale e Clinica, Università "Magna Graecia", Catanzaro, Italia
| | - Nicola Rinaldo
- Biogem scarl, Instituto di Rihe Genetiche "Gaetano Salvatore", Ariano Irpino, Italia
| | - Duarte Mendes Oliveira
- Dipartimento di Medicina Sperimentale e Clinica, Università "Magna Graecia", Catanzaro, Italia
| | - Maria Ravo
- Laboratorio di Medicina Molecolare e Genomica, Facoltà di Medicina e Chirurgia, Università di Salerno, Baronissi, Italia
| | - Alessandro Weisz
- Laboratorio di Medicina Molecolare e Genomica, Facoltà di Medicina e Chirurgia, Università di Salerno, Baronissi, Italia
| | - Michele Ceccarelli
- Dipartimento di Studi Biologici e Ambientali, Università del Sannio, Benevento, Italia
| | - Elvira Caira
- Dipartimento di Medicina Sperimentale e Clinica, Università "Magna Graecia", Catanzaro, Italia
| | - Antonia Rizzuto
- Dipartimento di Scienze Mediche e Chirurgiche, Università "Magna Graecia", Catanzaro, Italia
| | - Pietro Zoppoli
- Dipartimento di Medicina Sperimentale e Clinica, Università "Magna Graecia", Catanzaro, Italia
| | - Donatella Malanga
- Dipartimento di Medicina Sperimentale e Clinica, Università "Magna Graecia", Catanzaro, Italia
| | - Giuseppe Viglietto
- Dipartimento di Medicina Sperimentale e Clinica, Università "Magna Graecia", Catanzaro, Italia.,Biogem scarl, Instituto di Rihe Genetiche "Gaetano Salvatore", Ariano Irpino, Italia
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63
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Perifosine enhances bevacizumab-induced apoptosis and therapeutic efficacy by targeting PI3K/AKT pathway in a glioblastoma heterotopic model. Apoptosis 2017; 22:1025-1034. [DOI: 10.1007/s10495-017-1382-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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64
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Wang Z, Han Z, Tao J, Wang J, Liu X, Zhou W, Xu Z, Zhao C, Wang Z, Tan R, Gu M. Role of endothelial-to-mesenchymal transition induced by TGF-β1 in transplant kidney interstitial fibrosis. J Cell Mol Med 2017; 21:2359-2369. [PMID: 28374926 PMCID: PMC5618680 DOI: 10.1111/jcmm.13157] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 02/12/2017] [Indexed: 01/18/2023] Open
Abstract
Chronic allograft dysfunction (CAD) induced by kidney interstitial fibrosis is the main cause of allograft failure in kidney transplantation. Endothelial‐to‐mesenchymal transition (EndMT) may play an important role in kidney fibrosis. We, therefore, undertook this study to characterize the functions and potential mechanism of EndMT in transplant kidney interstitial fibrosis. Proteins and mRNAs associated with EndMT were examined in human umbilical vein endothelial cells (HUVECs) treated with transforming growth factor‐beta1 (TGF‐β1) at different doses or at different intervals with western blotting, qRT‐PCR and ELISA assays. Cell motility and migration were evaluated with motility and migration assays. The mechanism of EndMT induced by TGF‐β1 was determined by western blotting analysis of factors involved in various canonical and non‐canonical pathways. In addition, human kidney tissues from control and CAD group were also examined for these proteins by HE, Masson's trichrome, immunohistochemical, indirect immunofluorescence double staining and western blotting assays. TGF‐β1 significantly promoted the development of EndMT in a time‐dependent and dose‐dependent manner and promoted the motility and migration ability of HUVECs. The TGF‐β/Smad and Akt/mTOR/p70S6K signalling pathways were found to be associated with the pathogenesis of EndMT induced by TGF‐β1, which was also proven in vivo by the analysis of specimens from the control and CAD groups. EndMT may promote transplant kidney interstitial fibrosis by targetting the TGF‐β/Smad and Akt/mTOR/p70S6K signalling pathways, and hence, result in the development of CAD in kidney transplant recipients.
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Affiliation(s)
- Zijie Wang
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Zhijian Han
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Jun Tao
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Jun Wang
- Department of Urology, the Affiliated Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China
| | - Xuzhong Liu
- Department of Urology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, China
| | - Wanli Zhou
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Zhen Xu
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Chunchun Zhao
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Zengjun Wang
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Ruoyun Tan
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Min Gu
- Department of Urology, the First Affiliated Hospital, Nanjing Medical University, Nanjing, China
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65
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Nawaz Z, Patil V, Paul Y, Hegde AS, Arivazhagan A, Santosh V, Somasundaram K. PI3 kinase pathway regulated miRNome in glioblastoma: identification of miR-326 as a tumour suppressor miRNA. Mol Cancer 2016; 15:74. [PMID: 27871300 PMCID: PMC5117574 DOI: 10.1186/s12943-016-0557-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 11/03/2016] [Indexed: 12/02/2022] Open
Abstract
Background Glioblastomas (GBM) continue to remain one of the most dreaded tumours that are highly infiltrative in nature and easily preclude comprehensive surgical resection. GBMs pose an intricate etiology as they are being associated with a plethora of genetic and epigenetic lesions. Misregulation of the PI3 kinase pathway is one of the most familiar events in GBM. While the PI3 kinase signalling regulated pathways and genes have been comprehensively studied, its impact on the miRNome is yet to be explored. The objective of this study was to elucidate the PI3 kinase pathway regulated miRNAs in GBM. Methods miRNA expression profiling was conducted to monitor the differentially regulated miRNAs upon PI3 kinase pathway abrogation. qRT-PCR was used to measure the abundance of miR-326 and its host gene encoded transcript. Proliferation assay, colony suppression assay and wound healing assay were carried out in pre-miR transfected cells to investigate its role in malignant transformation. Potential targets of miR-326 were identified by transcriptome analysis of miR-326 overexpressing cells by whole RNA sequencing and selected targets were validated. Several publically available data sets were used for various investigations described above. Results We identified several miRNA that were regulated by PI3 kinase pathway. miR-326, a GBM downregulated miRNA, was validated as one of the miRNAs whose expression was alleviated upon abrogation of the PI3 kinase pathway. Overexpression of miR-326 resulted in reduced proliferation, colony suppression and hindered the migration capacity of glioma cells. Arrestin, Beta 1 (ARRB1), the host gene of miR-326, was also downregulated in GBM and interestingly, the expression of ARRB1 was also alleviated upon inhibition of the PI3 kinase pathway, indicating similar regulation pattern. More importantly, miR-326 exhibited a significant positive correlation with ARRB1 in terms of its expression. Transcriptome analysis upon miR-326 overexpression coupled with integrative bioinformatics approach identified several putative targets of miR-326. Selected targets were validated and interestingly found to be upregulated in GBM. Conclusions Taken together, our study uncovered the PI3 kinase regulated miRNome in GBM. miR-326, a PI3 kinase pathway inhibited miRNA, was demonstrated as a tumour suppressor miRNA in GBM. Electronic supplementary material The online version of this article (doi:10.1186/s12943-016-0557-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zahid Nawaz
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India
| | - Vikas Patil
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India
| | - Yashna Paul
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India
| | - Alangar S Hegde
- Department of Neurosurgery, Sri Satya Sai Institute of Higher Medical Sciences, Bangalore, 560066, India
| | - Arimappamagan Arivazhagan
- Departments of Neurosurgery, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Vani Santosh
- Departments of Neuropathology, National Institute of Mental Health and Neuro Sciences, Bangalore, 560029, India
| | - Kumaravel Somasundaram
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012, India.
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66
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Nozhat Z, Hedayati M. PI3K/AKT Pathway and Its Mediators in Thyroid Carcinomas. Mol Diagn Ther 2016; 20:13-26. [PMID: 26597586 DOI: 10.1007/s40291-015-0175-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Thyroid malignancies are the most common endocrine system carcinomas, with four histopathological forms. The phosphoinositide 3-kinase-protein kinase B/AKT (PI3K-PKB/AKT) pathway is one of the most critical molecular signaling pathways implicated in key cellular processes. Its continuous activation by several aberrant receptor tyrosine kinases (RTKs) and genetic mutations in its downstream effectors result in high cell proliferation in a broad number of cancers, including thyroid carcinomas. In this review article, the role of different signaling pathways of PI3K/AKT in thyroid cancers, with the emphasis on the PI3K/AKT/mammalian target of rapamycin (mTOR), PI3K/AKT/forkhead box O (FOXO) and PI3K/AKT/phosphatase and tensin homolog deleted on chromosome ten (PTEN) pathways, and various therapeutic strategies targeting these pathways have been summarized. In most of the in vitro studies, agents inhibiting mTOR in monotherapy or in combination with chemotherapy for thyroid malignancies have been introduced as promising anticancer therapies. FOXOs and PTEN are two outstanding downstream targets of the PI3K/AKT pathway. At the present time, no study has been undertaken to consider thyroid cancer treatment via FOXOs and PTEN targeting. According to the critical role of these proteins in cell cycle arrest, it seems that a treatment strategy based on the combination of FOXOs or PTEN activity induction with PI3K/AKT downstream mediators (e.g., mTOR) inhibition will be beneficial and promising in thyroid cancer treatment.
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Affiliation(s)
- Zahra Nozhat
- Cellular and Molecular Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Biotechnology Department, School of Advanced Technology in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehdi Hedayati
- Cellular and Molecular Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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67
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Bhattacharya S, McElhanon KE, Gushchina LV, Weisleder N. Role of phosphatidylinositol-4,5-bisphosphate 3-kinase signaling in vesicular trafficking. Life Sci 2016; 167:39-45. [PMID: 27760304 DOI: 10.1016/j.lfs.2016.10.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/13/2016] [Accepted: 10/14/2016] [Indexed: 02/07/2023]
Abstract
Phosphatidylinositol-4,5-bisphosphate 3-kinases (PI3Ks) are regulatory enzymes involved in the generation of lipid species that modulate cellular signaling pathways through downstream effectors to influence a variety of cellular functions. Years of intensive study of PI3Ks have produced a significant body of literature in many areas, including that PI3K can mediate intracellular vesicular trafficking and through these actions contribute to a number of important physiological functions. This review focuses on the crucial roles that PI3K and AKT, a major downstream partner of PI3K, play in the regulation of vesicle trafficking during various forms of vesicular endocytosis and exocytosis.
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Affiliation(s)
- Sayak Bhattacharya
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, 473 W. 12th Ave., Columbus, OH 43210-1252, United States
| | - Kevin E McElhanon
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, 473 W. 12th Ave., Columbus, OH 43210-1252, United States
| | - Liubov V Gushchina
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, 473 W. 12th Ave., Columbus, OH 43210-1252, United States
| | - Noah Weisleder
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, 473 W. 12th Ave., Columbus, OH 43210-1252, United States.
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68
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Fix DK, Hardee JP, Bateman TA, Carson JA. Effect of irradiation on Akt signaling in atrophying skeletal muscle. J Appl Physiol (1985) 2016; 121:917-924. [PMID: 27562841 DOI: 10.1152/japplphysiol.00218.2016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 08/18/2016] [Indexed: 12/15/2022] Open
Abstract
Muscle irradiation (IRR) exposure can accompany unloading during spaceflight or cancer treatment, and this has been shown to be sufficient by itself to induce skeletal muscle signaling associated with a remodeling response. Although protein kinase B/Akt has an established role in the regulation of muscle growth and metabolism, there is a limited understanding of how Akt signaling in unloaded skeletal muscle is affected by IRR. Therefore, we examined the combined effects of acute IRR and short-term unloading on muscle Akt signaling. Female C57BL/6 mice were subjected to load bearing or hindlimb suspension (HS) for 5 days (n = 6/group). A single, unilateral hindlimb IRR dose (0.5 Gy X-ray) was administered on day 3 Gastrocnemius muscle protein expression was examined. HS resulted in decreased AktT308 phosphorylation, whereas HS+IRR resulted in increased AktT308 phosphorylation above baseline. HS resulted in reduced AktS473 phosphorylation, which was rescued by HS+IRR. Interestingly, IRR alone resulted in increased phosphorylation of AktS473, but not that of AktT308 HS resulted in decreased mTORC1 signaling, and this suppression was not altered by IRR. Both IRR and HS resulted in increased MuRF-1 expression, whereas atrogin-1 expression was not affected by either condition. These results demonstrate that either IRR alone or when combined with HS can differentially affect Akt phosphorylation, but IRR did not disrupt suppressed mTORC1 signaling by HS. Collectively, these findings highlight that a single IRR dose is sufficient to disrupt the regulation of Akt signaling in atrophying skeletal muscle.
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Affiliation(s)
- Dennis K Fix
- Integrative Muscle Biology Laboratory, Division of Applied Physiology, Department of Exercise Science, University of South Carolina, Columbia, South Carolina; and
| | - Justin P Hardee
- Integrative Muscle Biology Laboratory, Division of Applied Physiology, Department of Exercise Science, University of South Carolina, Columbia, South Carolina; and
| | - Ted A Bateman
- Departments of Biomedical Engineering and Radiation Oncology, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina
| | - James A Carson
- Integrative Muscle Biology Laboratory, Division of Applied Physiology, Department of Exercise Science, University of South Carolina, Columbia, South Carolina; and
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69
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Hirsova P, Ibrabim SH, Gores GJ, Malhi H. Lipotoxic lethal and sublethal stress signaling in hepatocytes: relevance to NASH pathogenesis. J Lipid Res 2016; 57:1758-1770. [PMID: 27049024 PMCID: PMC5036373 DOI: 10.1194/jlr.r066357] [Citation(s) in RCA: 186] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 04/05/2016] [Indexed: 12/12/2022] Open
Abstract
The accumulation of lipids is a histologic and biochemical hallmark of obesity-associated nonalcoholic fatty liver disease (NAFLD). A subset of NALFD patients develops progressive liver disease, termed nonalcoholic steatohepatitis, which is characterized by hepatocellular apoptosis and innate immune system-mediated inflammation. These responses are orchestrated by signaling pathways that can be activated by lipids, directly or indirectly. In this review, we discuss palmitate- and lysophosphatidylcholine (LPC)-induced upregulation of p53-upregulated modulator of apoptosis and cell-surface expression of the death receptor TNF-related apoptosis-inducing ligand receptor 2. Next, we review the activation of stress-induced kinases, mixed lineage kinase 3, and c-Jun N-terminal kinase, and the activation of endoplasmic reticulum stress response and its downstream proapoptotic effector, CAAT/enhancer binding homologous protein, by palmitate and LPC. Moreover, the activation of these stress signaling pathways is linked to the release of proinflammatory, proangiogenic, and profibrotic extracellular vesicles by stressed hepatocytes. This review discusses the signaling pathways induced by lethal and sublethal lipid overload that contribute to the pathogenesis of NAFLD.
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Affiliation(s)
- Petra Hirsova
- Divisions of Gastroenterology and Hepatology Mayo Clinic, Rochester, MN 55905
| | - Samar H Ibrabim
- Pediatric Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN 55905
| | - Gregory J Gores
- Divisions of Gastroenterology and Hepatology Mayo Clinic, Rochester, MN 55905.
| | - Harmeet Malhi
- Divisions of Gastroenterology and Hepatology Mayo Clinic, Rochester, MN 55905.
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Waseem M, Khan I, Iqbal H, Eijaz S, Usman S, Ahmed N, Alam G, Salim A. Hypoxic Preconditioning Improves the Therapeutic Potential of Aging Bone Marrow Mesenchymal Stem Cells in Streptozotocin-Induced Type-1 Diabetic Mice. Cell Reprogram 2016; 18:344-355. [PMID: 27500307 DOI: 10.1089/cell.2016.0002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Insulin replacement is the current therapeutic option for type-1 diabetes. However, exogenous insulin cannot precisely represent the normal pattern of insulin secretion. Another therapeutic strategy is transplantation of pancreatic islets, but this is limited by immune rejection, intrinsic complications, and lack of donor availability. Stem cell therapy that results in the regeneration of insulin-producing cells represents an attractive choice. However, with advancing age, stem cells also undergo senescence, which leads to changes in the function of various cellular processes that result in a decrease in the regeneration potential of these aging stem cells. In this study, the effect of young and aging mesenchymal stem cells (MSCs) on the regeneration of pancreatic beta cells in streptozotocin (STZ)-induced type-1 diabetic mice was observed after hypoxic preconditioning. Hypoxia was chemically induced by 2, 4-dinitrophenol (DNP). Plasma insulin and glucose levels were measured at various time intervals, and pancreatic sections were analyzed histochemically. The effect of DNP was also analyzed on apoptosis of MSCs by flow cytometry and on gene expression of certain growth factors by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). We observed that hypoxic preconditioning caused changes in the gene expression levels of growth factors in both young and aging MSCs. Young MSCs showed significant regeneration potential compared with the aging cells in vivo. However, hypoxic preconditioning was able to improve the regeneration potential of aging MSCs. It is concluded from the present study that the regeneration potential of aging MSCs into pancreatic β-cells can be enhanced by hypoxic preconditioning, which causes changes in the gene expression of certain growth factors.
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Affiliation(s)
- Muhammad Waseem
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
| | - Irfan Khan
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
| | - Hana'a Iqbal
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
| | - Sana Eijaz
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
| | - Shumaila Usman
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
| | - Nazia Ahmed
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
| | - Gulzar Alam
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
| | - Asmat Salim
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi , Karachi, Pakistan
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Chami B, Steel AJ, De La Monte SM, Sutherland GT. The rise and fall of insulin signaling in Alzheimer's disease. Metab Brain Dis 2016; 31:497-515. [PMID: 26883429 DOI: 10.1007/s11011-016-9806-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/03/2016] [Indexed: 02/06/2023]
Abstract
The prevalence of both diabetes and Alzheimer's disease (AD) are reaching epidemic proportions worldwide. Alarmingly, diabetes is also a risk factor for Alzheimer's disease. The AD brain is characterised by the accumulation of peptides called Aβ as plaques in the neuropil and hyperphosphorylated tau protein in the form of neurofibrillary tangles within neurons. How diabetes confers risk is unknown but a simple linear relationship has been proposed whereby the hyperinsulinemia associated with type 2 diabetes leads to decreased insulin signaling in the brain, with downregulation of the PI3K/AKT signalling pathway and its inhibition of the major tau kinase, glycogen synthase kinase 3β. The earliest studies of post mortem AD brain tissue largely confirmed this cascade of events but subsequent studies have generally found either an upregulation of AKT activity, or that the relationship between insulin signaling and AD is independent of glycogen synthase kinase 3β altogether. Given the lack of success of beta-amyloid-reducing therapies in clinical trials, there is intense interest in finding alternative or adjunctive therapeutic targets for AD. Insulin signaling is a neuroprotective pathway and represents an attractive therapeutic option. However, this incredibly complex signaling pathway is not fully understood in the human brain and particularly in the context of AD. Here, we review the ups and downs of the research efforts aimed at understanding how diabetes modifies AD risk.
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Affiliation(s)
- B Chami
- Redox Biology, The University of Sydney, Sydney, NSW,, 2006, Australia
| | - A J Steel
- Neuropathology Group, Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia
| | - S M De La Monte
- Department of Neurology, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
- Department of Neurosurgery, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
- Department of Pathology, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
| | - Greg T Sutherland
- Neuropathology Group, Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia.
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Tan HK, Muhammad TST, Tan ML. 14-Deoxy-11,12-didehydroandrographolide induces DDIT3-dependent endoplasmic reticulum stress-mediated autophagy in T-47D breast carcinoma cells. Toxicol Appl Pharmacol 2016; 300:55-69. [DOI: 10.1016/j.taap.2016.03.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/18/2016] [Accepted: 03/30/2016] [Indexed: 12/11/2022]
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73
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Fischer P, Preiss A, Nagel AC. A triangular connection between Cyclin G, PP2A and Akt1 in the regulation of growth and metabolism in Drosophila. Fly (Austin) 2016; 10:11-8. [PMID: 26980713 PMCID: PMC4934794 DOI: 10.1080/19336934.2016.1162362] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Size and weight control is a tightly regulated process, involving the highly conserved Insulin receptor/target of rapamycin (InR/TOR) signaling cascade. We recently identified Cyclin G (CycG) as an important modulator of InR/TOR signaling activity in Drosophila. cycG mutant flies are underweight and show a disturbed fat metabolism resembling TOR mutants. In fact, InR/TOR signaling activity is disturbed in cycG mutants at the level of Akt1, the central kinase linking InR and TORC1. Akt1 is negatively regulated by protein phosphatase PP2A. Notably the binding of the PP2A B′-regulatory subunit Widerborst (Wdb) to Akt1 is differentially regulated in cycG mutants, presumably by a direct interaction of CycG and Wdb. Since the metabolic defects of cycG mutant animals are abrogated by a concomitant loss of Wdb, CycG presumably influences Akt1 activity at the PP2A nexus. Here we show that Well rounded (Wrd), another B' subunit of PP2A in Drosophila, binds CycG similar to Wdb, and that its loss ameliorates some, but not all, of the metabolic defects of cycG mutants. We propose a model, whereby the binding of CycG to a particular B′-regulatory subunit influences the tissue specific activity of PP2A, required for the fine tuning of the InR/TOR signaling cascade in Drosophila.
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Affiliation(s)
- Patrick Fischer
- a Institute of Genetics, University of Hohenheim , Stuttgart , Germany
| | - Anette Preiss
- a Institute of Genetics, University of Hohenheim , Stuttgart , Germany
| | - Anja C Nagel
- a Institute of Genetics, University of Hohenheim , Stuttgart , Germany
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Li D, Chen H, Luo XH, Sun Y, Xia W, Xiong YC. CX3CR1-Mediated Akt1 Activation Contributes to the Paclitaxel-Induced Painful Peripheral Neuropathy in Rats. Neurochem Res 2016; 41:1305-14. [PMID: 26961886 DOI: 10.1007/s11064-016-1827-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 12/03/2015] [Accepted: 01/04/2016] [Indexed: 12/11/2022]
Abstract
Painful peripheral neuropathy is a serious dose-limiting side effect of paclitaxel therapy, which unfortunately often happens during the optimal clinical management of chemotherapy in cancer patients. Currently the underlying mechanisms of the painful peripheral neuropathy remain largely unknown. Here, we found that paclitaxel treatment (3 × 8 mg/kg, cumulative dose 24 mg/kg) upregulated the expression of CX3CR1 and phosphorylated Akt1 in DRG and spinal dorsal horn. Blocking of Akt1 pathway activation with different inhibitor (MK-2206 or LY294002) significantly attenuated mechanical allodynia and thermal hyperalgesia induced by paclitaxel. Furthermore, inhibition of CX3CR1 by using neutralizing antibody not only prevented Akt1 activation in DRG and spinal dorsal horn but also alleviated pain-related behavior induced by paclitaxel treatment. This study suggested that CX3CR1/Akt1 signaling pathway may be a potential target for prevention and reversion of the painful peripheral neuropathy induced by paclitaxel.
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Affiliation(s)
- Dai Li
- Department of Anesthesiology and Critical Care, The First Affiliated Hospital, Second Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Hui Chen
- Department of Anesthesiology and Critical Care, The First Affiliated Hospital, Second Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China
| | - Xiao-Huan Luo
- Center For Reproductive Medicine, Guangzhou First People's Hospital, Guangzhou Medical University, No.1 Panfu Road, Guangzhou, 510180, People's Republic of China
| | - Yang Sun
- Department of Pain, Branch of The First Affiliate Hospital of Xinjiang Medical University, Changji, People's Republic of China
| | - Wei Xia
- Center For Reproductive Medicine, Guangzhou First People's Hospital, Guangzhou Medical University, No.1 Panfu Road, Guangzhou, 510180, People's Republic of China.
| | - Yuan-Chang Xiong
- Department of Anesthesiology and Critical Care, The First Affiliated Hospital, Second Military Medical University, 168 Changhai Road, Shanghai, 200433, People's Republic of China.
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Costa AF, Gomes SZ, Lorenzon-Ojea AR, Martucci M, Faria MR, Pinto DDS, Oliveira SF, Ietta F, Paulesu L, Bevilacqua E. Macrophage migration inhibitory factor induces phosphorylation of Mdm2 mediated by phosphatidylinositol 3-kinase/Akt kinase: Role of this pathway in decidual cell survival. Placenta 2016; 41:27-38. [PMID: 27208405 DOI: 10.1016/j.placenta.2016.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/25/2016] [Accepted: 03/01/2016] [Indexed: 01/10/2023]
Abstract
The phosphatidylinositol 3-kinase (PI3K)/Akt pathway has an anti-apoptotic effect through several downstream targets, which includes activation of the transformed mouse 3T3 cell double-minute 2 (Mdm2) protein, its translocation to the nucleus and degradation of the tumor suppressor p53. We show that Mif, the Macrophage Migration Inhibitory Factor, an important cytokine at the maternal fetal interface in several species, triggers phosphorylation of Mdm2 protein in a PI3K/Akt-dependent manner, thereby preventing apoptosis in cultured mouse decidual cells. Inhibition of Akt and PI3K suppresses the pathway. Mif treatment also changes the nuclear translocation of p53 and interferes with the apoptotic fate of these cells when challenged with reactive oxygen species. In conclusion, an important mechanism has been found underlying decidual cell survival through Akt signaling pathway activated by Mif, suggesting a role for this cytokine in decidual homeostasis and in the integrity of the maternal-fetal barrier that is essential for successful gestation.
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Affiliation(s)
- Adriana Fraga Costa
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Stomatology, Dental School, University of São Paulo, São Paulo, Brazil
| | - Sara Zago Gomes
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Aline R Lorenzon-Ojea
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Mariane Martucci
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Miriam Rubio Faria
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Sergio F Oliveira
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Francesca Ietta
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Luana Paulesu
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Estela Bevilacqua
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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Bénard L, Oh JG, Cacheux M, Lee A, Nonnenmacher M, Matasic DS, Kohlbrenner E, Kho C, Pavoine C, Hajjar RJ, Hulot JS. Cardiac Stim1 Silencing Impairs Adaptive Hypertrophy and Promotes Heart Failure Through Inactivation of mTORC2/Akt Signaling. Circulation 2016; 133:1458-71; discussion 1471. [PMID: 26936863 DOI: 10.1161/circulationaha.115.020678] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 02/25/2016] [Indexed: 01/26/2023]
Abstract
BACKGROUND Stromal interaction molecule 1 (STIM1) is a dynamic calcium signal transducer implicated in hypertrophic growth of cardiomyocytes. STIM1 is thought to act as an initiator of cardiac hypertrophic response at the level of the sarcolemma, but the pathways underpinning this effect have not been examined. METHODS AND RESULTS To determine the mechanistic role of STIM1 in cardiac hypertrophy and during the transition to heart failure, we manipulated STIM1 expression in mice cardiomyocytes by using in vivo gene delivery of specific short hairpin RNAs. In 3 different models, we found that Stim1 silencing prevents the development of pressure overload-induced hypertrophy but also reverses preestablished cardiac hypertrophy. Reduction in STIM1 expression promoted a rapid transition to heart failure. We further showed that Stim1 silencing resulted in enhanced activity of the antihypertrophic and proapoptotic GSK-3β molecule. Pharmacological inhibition of glycogen synthase kinase-3 was sufficient to reverse the cardiac phenotype observed after Stim1 silencing. At the level of ventricular myocytes, Stim1 silencing or inhibition abrogated the capacity for phosphorylation of Akt(S473), a hydrophobic motif of Akt that is directly phosphorylated by mTOR complex 2. We found that Stim1 silencing directly impaired mTOR complex 2 kinase activity, which was supported by a direct interaction between STIM1 and Rictor, a specific component of mTOR complex 2. CONCLUSIONS These data support a model whereby STIM1 is critical to deactivate a key negative regulator of cardiac hypertrophy. In cardiomyocytes, STIM1 acts by tuning Akt kinase activity through activation of mTOR complex 2, which further results in repression of GSK-3β activity.
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Affiliation(s)
- Ludovic Bénard
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Jae Gyun Oh
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Marine Cacheux
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Ahyoung Lee
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Mathieu Nonnenmacher
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Daniel S Matasic
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Erik Kohlbrenner
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Changwon Kho
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Catherine Pavoine
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Roger J Hajjar
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.)
| | - Jean-Sébastien Hulot
- From Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY (L.B., J.G.O., M.C., A.L., M.N., D.S.M., E.K., C.W.K., R.J.H., J.-S.H.); and Sorbonne Universités, UPMC Univ Paris 06, AP-HP, Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière Hospital, Paris, France (C.P., J.-S.H.).
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Sampson LL, Davis AK, Grogg MW, Zheng Y. mTOR disruption causes intestinal epithelial cell defects and intestinal atrophy postinjury in mice. FASEB J 2015; 30:1263-75. [PMID: 26631481 DOI: 10.1096/fj.15-278606] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/16/2015] [Indexed: 12/21/2022]
Abstract
Intestinal stem cells (ISCs) drive small intestinal epithelial homeostasis and regeneration. Mechanistic target of rapamycin (mTOR) regulates stem and progenitor cell metabolism and is frequently dysregulated in human disease, but its physiologic functions in the mammalian small intestinal epithelium remain poorly defined. We disrupted the genes mTOR, Rptor, Rictor, or both Rptor and Rictor in mouse ISCs, progenitors, and differentiated intestinal epithelial cells (IECs) using Villin-Cre. Mutant tissues and wild-type or heterozygous littermate controls were analyzed by histologic immunostaining, immunoblots, and proliferation assays. A total of 10 Gy irradiation was used to injure the intestinal epithelium and induce subsequent crypt regeneration. We report that mTOR supports absorptive enterocytes and secretory Paneth and goblet cell function while negatively regulating chromogranin A-positive enteroendocrine cell number. Through additional Rptor, Rictor, and Rptor/Rictor mutant mouse models, we identify mechanistic target of rapamycin complex 1 as the major IEC regulatory pathway, but mechanistic target of rapamycin complex 2 also contributes to ileal villus maintenance and goblet cell size. Homeostatic adult small intestinal crypt cell proliferation, survival, and canonical wingless-int (WNT) activity are not mTOR dependent, but Olfm4(+) ISC/progenitor population maintenance and crypt regeneration postinjury require mTOR. Overall, we conclude that mTOR regulates multiple IEC lineages and promotes stem and progenitor cell activity during intestinal epithelium repair postinjury.
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Affiliation(s)
- Leesa L Sampson
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Ashley K Davis
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Matthew W Grogg
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Yi Zheng
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
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78
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Chen H, Li Y, Shi J, Song W. Role and mechanism of insulin-like growth factor 2 on the proliferation of human trophoblasts in vitro. J Obstet Gynaecol Res 2015; 42:44-51. [PMID: 26554875 DOI: 10.1111/jog.12853] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 08/05/2015] [Accepted: 08/16/2015] [Indexed: 12/24/2022]
Abstract
AIM To study the effect and relevant molecular mechanisms of insulin-like growth factor 2 (IGF2) on the proliferative activity of first trimester human trophoblasts in vitro. MATERIALS AND METHODS Extravillous cytotrophoblasts (EVCTs) were isolated and cultured. Cells were cultured with IGF2 at different concentrations and the proliferative activity was measured using methyl thiazolyl tretrazolium assay. LY294002, a specific inhibitor of the phosphatidylinositol 3-kinase (PI3K), was used as an indirect indicator of the possible involvement of the PI3K signal pathway. We tested the apoptosis rate using flow cytometry technology influenced by IGF2 with or without LY294002. The effects of IGF2 on phosphorylation of key cell signaling proteins (protein kinase B [AKT] and phosphorylated AKT) in EVCTs were examined by western blot analysis with or without LY294002. RESULTS There was a significant difference between the IGF2 group above 10 nM and the control group (P < 0.05). LY294002 (10 μM) not only inhibited the proliferative activity of EVCT, but also significantly restrained the effect on EVCTs (P < 0.05). In vitro data proved that the apoptosis rate decreased when IGF2 was added (P < 0.05), but increased when inhibited by LY294002 (P < 0.05). After incubation with IGF2, AKT phosphorylation increased compared to incubation without IGF2 treatment (P < 0.05). LY294002 activation reduced the IGF2-induced effects (P < 0.05). CONCLUSIONS Our data suggest that IGF2 enhances EVCT proliferation and inhibits apoptosis. The PI3K/AKT pathway is an important signaling pathway in the proliferative activity of EVCTs on early human pregnancy in vitro.
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Affiliation(s)
- Huiyue Chen
- Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University, Shenyang, China
| | - Yating Li
- Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University, Shenyang, China
| | - Jia Shi
- Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University, Shenyang, China
| | - Weiwei Song
- Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University, Shenyang, China
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Expression, Crystallization and Preliminary X-ray Diffraction Analyses of Med-ORF10 in the Biosynthetic Pathway of an Antitumor Antibiotic Medermycin. Protein J 2015; 34:404-10. [DOI: 10.1007/s10930-015-9635-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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80
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Choi S, Anderson RA. IQGAP1 is a phosphoinositide effector and kinase scaffold. Adv Biol Regul 2015; 60:29-35. [PMID: 26554303 DOI: 10.1016/j.jbior.2015.10.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 10/05/2015] [Accepted: 10/06/2015] [Indexed: 01/16/2023]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PI4,5P2) is a lipid messenger that regulates a wide variety of cellular functions. The majority of cellular PI4,5P2 is generated by isoforms of the type I phosphatidylinositol phosphate kinases (PIPKI) that are generated from three genes, and each PIPKI isoform has a unique distribution and function in cells. It has been shown that the signaling specificity of PI4,5P2 can be determined by a physical association of PIPKs with PI4,5P2 effectors. IQGAP1 is newly identified as an interactor of multiple isoforms of PIPKs. Considering the versatile roles of IQGAP1 in cellular signaling pathways, IQGAP1 may confer isoform-specific roles of PIPKs in distinct cellular locations. In this mini review, the emerging roles of PIPKs that are regulated by an association with IQGAP1 will be summarized. Focuses will be on cell migration, vesicle trafficking, cell signaling, and nuclear events.
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Affiliation(s)
- Suyong Choi
- University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Richard A Anderson
- University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA.
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81
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Gupta SC, Singh R, Pochampally R, Watabe K, Mo YY. Acidosis promotes invasiveness of breast cancer cells through ROS-AKT-NF-κB pathway. Oncotarget 2015; 5:12070-82. [PMID: 25504433 PMCID: PMC4322981 DOI: 10.18632/oncotarget.2514] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 09/24/2014] [Indexed: 01/24/2023] Open
Abstract
It is well known that acidic microenvironment promotes tumorigenesis, however, the underlying mechanism remains largely unknown. In the present study, we show that acidosis promotes invasiveness of breast cancer cells through a series of signaling events. First, our study indicates that NF-κB is a key factor for acidosis-induced cell invasion. Acidosis activates NF-κB without affecting STAT3 activity; knockdown of NF-κB p65 abrogates the acidosis-induced invasion activity. Next, we show that the activation of NF-κB is mediated through phosphorylation and degradation of IκBα; and phosphorylation and nuclear translocation of p65. Upstream to NF-κB signaling, AKT is activated under acidic conditions. Moreover, acidosis induces generation of reactive oxygen species (ROS) which can be suppressed by ROS scavengers, reversing the acidosis-induced activation of AKT and NF-κB, and invasiveness. As a negative regulator of AKT, PTEN is oxidized and inactivated by the acidosis-induced ROS. Finally, inhibition of NADPH oxidase (NOX) suppresses acidosis-induced ROS production, suggesting involvement of NOX in acidosis-induced signaling cascade. Of considerable interest, acidosis-induced ROS production and activation of AKT and NF-κB can be only detected in cancer cells, but not in non-malignant cells. Together, these results demonstrate a cancer specific acidosis-induced signaling cascade in breast cancer cells, leading to cell invasion.
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Affiliation(s)
- Subash C Gupta
- Cancer Institute, University of Mississippi Medical Center, Jackson, MS. Department of Biochemistry, University of Mississippi Medical Center, Jackson, MS
| | - Ramesh Singh
- Cancer Institute, University of Mississippi Medical Center, Jackson, MS. Department of Biochemistry, University of Mississippi Medical Center, Jackson, MS
| | - Radhika Pochampally
- Cancer Institute, University of Mississippi Medical Center, Jackson, MS. Department of Biochemistry, University of Mississippi Medical Center, Jackson, MS
| | - Kounosuke Watabe
- Cancer Institute, University of Mississippi Medical Center, Jackson, MS. Department of Microbiology, University of Mississippi Medical Center, Jackson, MS
| | - Yin-Yuan Mo
- Cancer Institute, University of Mississippi Medical Center, Jackson, MS. Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS
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Shao J, Stout I, Hendriksen PJM, van Loveren H, Peijnenburg AACM, Volger OL. Protein phosphorylation profiling identifies potential mechanisms for direct immunotoxicity. J Immunotoxicol 2015; 13:97-107. [PMID: 25715851 DOI: 10.3109/1547691x.2015.1016635] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Signaling networks are essential elements that are involved in diverse cellular processes. One group of fundamental components in various signaling pathways concerns protein tyrosine kinases (PTK). Various toxicants have been demonstrated to exert their toxicity via modulation of tyrosine kinase activity. The present study aimed to identify common cellular signaling pathways that are involved in chemical-induced direct immunotoxicity. To this end, an antibody array-based profiling approach was applied to assess effects of five immunotoxicants, two immunosuppressive drugs and two non-immunotoxic control chemicals on the phosphorylation of 28 receptor tyrosine kinases and 11 crucial signaling nodes in Jurkat T-cells. The phosphorylation of ribosomal protein S6 (RPS6) and of kinases Akt, Src and p44/42 were found to be commonly regulated by immunotoxicants and/or immunosuppressive drugs (at least three compounds), with the largest effect observed upon RPS6. Flow cytometry and Western blotting were used to further examine the effect of the model immunotoxicant TBTO on the components of the mTOR-p70S6K-RPS6 pathway. These analyses revealed that both TBTO and the mTOR inhibitor rapamycin inactivate RPS6, but via different mechanisms. Finally, a comparison of the protein phosphorylation data to previously obtained transcriptome data of TBTO-treated Jurkat cells resulted in a good correlation at the pathway level and indicated that TBTO affects ribosome biogenesis and leukocyte migration. The effect of TBTO on the latter process was confirmed using a CXCL12 chemotaxis assay.
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Affiliation(s)
- Jia Shao
- a RIKILT-Institute of Food Safety, Wageningen University and Research Centre , Wageningen , the Netherlands .,b Department of Toxicogenomics , Maastricht University , the Netherlands .,c Netherlands Toxicogenomics Centre , the Netherlands , and
| | - Inge Stout
- a RIKILT-Institute of Food Safety, Wageningen University and Research Centre , Wageningen , the Netherlands
| | - Peter J M Hendriksen
- a RIKILT-Institute of Food Safety, Wageningen University and Research Centre , Wageningen , the Netherlands .,c Netherlands Toxicogenomics Centre , the Netherlands , and
| | - Henk van Loveren
- b Department of Toxicogenomics , Maastricht University , the Netherlands .,c Netherlands Toxicogenomics Centre , the Netherlands , and.,d National Institute for Public Health and the Environment (RIVM) , Bilthoven , the Netherlands
| | - Ad A C M Peijnenburg
- a RIKILT-Institute of Food Safety, Wageningen University and Research Centre , Wageningen , the Netherlands .,c Netherlands Toxicogenomics Centre , the Netherlands , and
| | - Oscar L Volger
- a RIKILT-Institute of Food Safety, Wageningen University and Research Centre , Wageningen , the Netherlands .,c Netherlands Toxicogenomics Centre , the Netherlands , and
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Kriplani N, Hermida MA, Brown ER, Leslie NR. Class I PI 3-kinases: Function and evolution. Adv Biol Regul 2015; 59:53-64. [PMID: 26159297 DOI: 10.1016/j.jbior.2015.05.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 05/25/2015] [Indexed: 06/04/2023]
Abstract
In many human cell types, the class I phosphoinositide 3-kinases play key roles in the control of diverse cellular processes including growth, proliferation, survival and polarity. This is achieved through their activation by many cell surface receptors, leading to the synthesis of the phosphoinositide lipid signal, PIP3, which in turn influences the function of numerous direct PIP3-binding proteins. Here we review PI3K pathway biology and analyse the evolutionary distribution of its components and their functions. The broad phylogenetic distribution of class I PI3Ks in metazoa, amoebozoa and choannoflagellates, implies that these enzymes evolved in single celled organisms and were later co-opted into metazoan intercellular communication. A similar distribution is evident for the AKT and Cytohesin groups of downstream PIP3-binding proteins, with other effectors and pathway components appearing to evolve later. The genomic and functional phylogeny of regulatory systems such as the PI3K pathway provides a framework to improve our understanding of the mechanisms by which key cellular processes are controlled in humans.
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Affiliation(s)
- Nisha Kriplani
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot Watt University, Edinburgh, EH14 4AS, UK
| | - Miguel A Hermida
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot Watt University, Edinburgh, EH14 4AS, UK
| | - Euan R Brown
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot Watt University, Edinburgh, EH14 4AS, UK
| | - Nicholas R Leslie
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot Watt University, Edinburgh, EH14 4AS, UK.
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Fischer P, La Rosa MK, Schulz A, Preiss A, Nagel AC. Cyclin G Functions as a Positive Regulator of Growth and Metabolism in Drosophila. PLoS Genet 2015; 11:e1005440. [PMID: 26274446 PMCID: PMC4537266 DOI: 10.1371/journal.pgen.1005440] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 07/13/2015] [Indexed: 01/15/2023] Open
Abstract
In multicellular organisms, growth and proliferation is adjusted to nutritional conditions by a complex signaling network. The Insulin receptor/target of rapamycin (InR/TOR) signaling cascade plays a pivotal role in nutrient dependent growth regulation in Drosophila and mammals alike. Here we identify Cyclin G (CycG) as a regulator of growth and metabolism in Drosophila. CycG mutants have a reduced body size and weight and show signs of starvation accompanied by a disturbed fat metabolism. InR/TOR signaling activity is impaired in cycG mutants, combined with a reduced phosphorylation status of the kinase Akt1 and the downstream factors S6-kinase and eukaryotic translation initiation factor 4E binding protein (4E-BP). Moreover, the expression and accumulation of Drosophila insulin like peptides (dILPs) is disturbed in cycG mutant brains. Using a reporter assay, we show that the activity of one of the first effectors of InR signaling, Phosphoinositide 3-kinase (PI3K92E), is unaffected in cycG mutants. However, the metabolic defects and weight loss in cycG mutants were rescued by overexpression of Akt1 specifically in the fat body and by mutants in widerborst (wdb), the B'-subunit of the phosphatase PP2A, known to downregulate Akt1 by dephosphorylation. Together, our data suggest that CycG acts at the level of Akt1 to regulate growth and metabolism via PP2A in Drosophila. Size and growth of an organism are adjusted to nutritional conditions by a complex regulatory network involving the Insulin receptor and TOR signaling cascades. Drosophila melanogaster has been used in the past as a genetically tractable model to unravel the complex circuitry by genetic means. We have identified CycG as an important player in the regulation of TOR signaling. CycG mutants are underweight in the midst of food and show typical signs of TOR defects. We provide evidence that CycG acts at the level of Akt1 kinase that links the Insulin receptor and TOR signaling cascades. Molecular and genetic data point to an interplay of CycG and phosphatase PP2A, a well established negative regulator of Akt1 activity. Moreover, CycG may influence PP2A-Akt1 binding. We propose that CycG, by impeding PP2A-Akt1 interaction, acts as a positive regulator of growth in Drosophila.
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Affiliation(s)
- Patrick Fischer
- Institute of Genetics, University of Hohenheim, Stuttgart, Germany
| | | | - Adriana Schulz
- Institute of Genetics, University of Hohenheim, Stuttgart, Germany
| | - Anette Preiss
- Institute of Genetics, University of Hohenheim, Stuttgart, Germany
| | - Anja C. Nagel
- Institute of Genetics, University of Hohenheim, Stuttgart, Germany
- * E-mail:
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85
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Bradley EW, Carpio LR, Newton AC, Westendorf JJ. Deletion of the PH-domain and Leucine-rich Repeat Protein Phosphatase 1 (Phlpp1) Increases Fibroblast Growth Factor (Fgf) 18 Expression and Promotes Chondrocyte Proliferation. J Biol Chem 2015; 290:16272-80. [PMID: 25953896 DOI: 10.1074/jbc.m114.612937] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Indexed: 01/14/2023] Open
Abstract
Endochondral ossification orchestrates formation of the vertebrate skeleton and is often induced during disease and repair processes of the musculoskeletal system. Here we show that the protein phosphatase Phlpp1 regulates endochondral ossification. Phlpp1 null mice exhibit decreased bone mass and notable changes in the growth plate, including increased BrdU incorporation and matrix production. Phosphorylation of known Phlpp1 substrates, Akt2, PKC, and p70 S6 kinase, were enhanced in ex vivo cultured Phlpp1(-/-) chondrocytes. Furthermore, Phlpp1 deficiency diminished FoxO1 levels leading to increased expression of Fgf18, Mek/Erk activity, and chondrocyte metabolic activity. Phlpp inhibitors also increased matrix content, Fgf18 production and Erk1/2 phosphorylation. Chemical inhibition of Fgfr-signaling abrogated elevated Erk1/2 phosphorylation and metabolic activity in Phlpp1-null cultures. These results demonstrate that Phlpp1 controls chondrogenesis via multiple mechanisms and that Phlpp1 inhibition could be a strategy to promote cartilage regeneration and repair.
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Affiliation(s)
| | | | - Alexandra C Newton
- the Department of Pharmacology, University of California, San Diego, La Jolla, California 92093
| | - Jennifer J Westendorf
- From the Department of Orthopedic Surgery, Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905 and
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86
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Nteeba J, Sanz-Fernandez MV, Rhoads RP, Baumgard LH, Ross JW, Keating AF. Heat Stress Alters Ovarian Insulin-Mediated Phosphatidylinositol-3 Kinase and Steroidogenic Signaling in Gilt Ovaries. Biol Reprod 2015; 92:148. [PMID: 25926439 DOI: 10.1095/biolreprod.114.126714] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 04/09/2015] [Indexed: 12/26/2022] Open
Abstract
Heat stress (HS) compromises a variety of reproductive functions in several mammalian species. Inexplicably, HS animals are frequently hyperinsulinemic despite marked hyperthermia-induced hypophagia. Our objectives were to determine the effects of HS on insulin signaling and components essential to steroid biosynthesis in the pig ovary. Female pigs (35 ± 4 kg) were exposed to constant thermoneutral (20°C; 35%-50% humidity; n = 6) or HS conditions (35°C; 20%-35% humidity; n = 6) for either 7 (n = 10) or 35 days (n = 12). After 7 days, HS increased (P < 0.05) ovarian mRNA abundance of the insulin receptor (INSR), insulin receptor substrate 1 (IRS1), protein kinase B subunit 1 (AKT1), low-density lipoprotein receptor (LDLR), luteinizing hormone receptor (LHCGR), and aromatase (CYP19a). After 35 days, HS increased INSR, IRS1, AKT1, LDLR, LHCGR, CYP19a, and steroidogenic acute regulatory protein (STAR) ovarian mRNA abundance. In addition, after 35 days, HS increased ovarian phosphorylated IRS1 (pIRS1), phosphorylated AKT (pAKT), STAR, and CYP19a protein abundance. Immunostaining analysis revealed similar localization of INSR and pAKT1 in the cytoplasmic membrane and oocyte cytoplasm, respectively, of all stage follicles, and in theca and granulosa cells. Collectively, these results demonstrate that HS alters ovarian insulin-mediated PI3K signaling pathway members, which likely impacts follicle activation and viability. In summary, environmentally induced HS is an endocrine-disrupting exposure that modifies ovarian physiology and potentially compromises production of ovarian hormones essential for fertility and pregnancy maintenance.
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Affiliation(s)
- Jackson Nteeba
- Department of Animal Science, Iowa State University, Ames, Iowa
| | | | - Robert P Rhoads
- Department of Animal and Poultry Sciences, Virginia Tech University, Blacksburg, Virginia
| | | | - Jason W Ross
- Department of Animal Science, Iowa State University, Ames, Iowa
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87
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Yu H, Littlewood T, Bennett M. Akt isoforms in vascular disease. Vascul Pharmacol 2015; 71:57-64. [PMID: 25929188 PMCID: PMC4728195 DOI: 10.1016/j.vph.2015.03.003] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 03/31/2015] [Indexed: 11/05/2022]
Abstract
The mammalian serine/threonine Akt kinases comprise three closely related isoforms: Akt1, Akt2 and Akt3. Akt activation has been implicated in both normal and disease processes, including in development and metabolism, as well as cancer and cardiovascular disease. Although Akt signalling has been identified as a promising therapeutic target in cancer, its role in cardiovascular disease is less clear. Importantly, accumulating evidence suggests that the three Akt isoforms exhibit distinct tissue expression profiles, localise to different subcellular compartments, and have unique modes of activation. Consistent with in vitro findings, genetic studies in mice show distinct effects of individual Akt isoforms on the pathophysiology of cardiovascular disease. This review summarises recent studies of individual Akt isoforms in atherosclerosis, vascular remodelling and aneurysm formation, to provide a comprehensive overview of Akt function in vascular disease.
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Affiliation(s)
- Haixiang Yu
- Division of Cardiovascular Medicine, University of Cambridge, Box 110, Addenbrooke's Centre for Clinical Investigation, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
| | - Trevor Littlewood
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
| | - Martin Bennett
- Division of Cardiovascular Medicine, University of Cambridge, Box 110, Addenbrooke's Centre for Clinical Investigation, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
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88
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Rotllan N, Wanschel AC, Fernández-Hernando A, Salerno AG, Offermanns S, Sessa WC, Fernández-Hernando C. Genetic Evidence Supports a Major Role for Akt1 in VSMCs During Atherogenesis. Circ Res 2015; 116:1744-52. [PMID: 25868464 DOI: 10.1161/circresaha.116.305895] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 04/13/2015] [Indexed: 12/29/2022]
Abstract
RATIONALE Coronary artery disease, the direct result of atherosclerosis, is the most common cause of death in Western societies. Vascular smooth muscle cell (VSMC) apoptosis occurs during the progression of atherosclerosis and in advanced lesions and promotes plaque necrosis, a common feature of high-risk/vulnerable atherosclerotic plaques. Akt1, a serine/threonine protein kinase, regulates several key endothelial cell and VSMC functions including cell growth, migration, survival, and vascular tone. Although global deficiency of Akt1 results in impaired angiogenesis and massive atherosclerosis, the specific contribution of VSMC Akt1 remains poorly characterized. OBJECTIVE To investigate the contribution of VSMC Akt1 during atherogenesis and in established atherosclerotic plaques. METHODS AND RESULTS We generated 2 mouse models in which Akt1 expression can be suppressed specifically in VSCMs before (Apoe(-/-)Akt1(fl/fl)Sm22α(CRE)) and after (Apoe(-/-)Akt1(fl/fl)SM-MHC-CreER(T2E)) the formation of atherosclerotic plaques. This approach allows us to interrogate the role of Akt1 during the initial and late steps of atherogenesis. The absence of Akt1 in VSMCs during the progression of atherosclerosis results in larger atherosclerotic plaques characterized by bigger necrotic core areas, enhanced VSMC apoptosis, and reduced fibrous cap and collagen content. In contrast, VSMC Akt1 inhibition in established atherosclerotic plaques does not influence lesion size but markedly reduces the relative fibrous cap area in plaques and increases VSMC apoptosis. CONCLUSIONS Akt1 expression in VSMCs influences early and late stages of atherosclerosis. The absence of Akt1 in VSMCs induces features of plaque vulnerability including fibrous cap thinning and extensive necrotic core areas. These observations suggest that interventions enhancing Akt1 expression specifically in VSMCs may lessen plaque progression.
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Affiliation(s)
- Noemi Rotllan
- From the Vascular Biology and Therapeutics Program (N.R., W.C.S., C.F-.H.), Integrative Cell Signaling and Neurobiology of Metabolism Program, Section of Comparative Medicine and Department of Pathology (N.R., C.F-.H.), Department of Pharmacology (W.C.S.), Yale University School of Medicine, New Haven, CT; Leon H. Charney Division of Cardiology and Cell Biology Departments of Medicine, New York University School of Medicine, NY (A.C.W., A.F.-H., A.G.S., C.F-.H.); and Department of Pharmacology, Max-Plank-Institute for Heart and Lung Research, Bad Nauheim, Germany (S.O.)
| | - Amarylis C Wanschel
- From the Vascular Biology and Therapeutics Program (N.R., W.C.S., C.F-.H.), Integrative Cell Signaling and Neurobiology of Metabolism Program, Section of Comparative Medicine and Department of Pathology (N.R., C.F-.H.), Department of Pharmacology (W.C.S.), Yale University School of Medicine, New Haven, CT; Leon H. Charney Division of Cardiology and Cell Biology Departments of Medicine, New York University School of Medicine, NY (A.C.W., A.F.-H., A.G.S., C.F-.H.); and Department of Pharmacology, Max-Plank-Institute for Heart and Lung Research, Bad Nauheim, Germany (S.O.)
| | - Ana Fernández-Hernando
- From the Vascular Biology and Therapeutics Program (N.R., W.C.S., C.F-.H.), Integrative Cell Signaling and Neurobiology of Metabolism Program, Section of Comparative Medicine and Department of Pathology (N.R., C.F-.H.), Department of Pharmacology (W.C.S.), Yale University School of Medicine, New Haven, CT; Leon H. Charney Division of Cardiology and Cell Biology Departments of Medicine, New York University School of Medicine, NY (A.C.W., A.F.-H., A.G.S., C.F-.H.); and Department of Pharmacology, Max-Plank-Institute for Heart and Lung Research, Bad Nauheim, Germany (S.O.)
| | - Alessandro G Salerno
- From the Vascular Biology and Therapeutics Program (N.R., W.C.S., C.F-.H.), Integrative Cell Signaling and Neurobiology of Metabolism Program, Section of Comparative Medicine and Department of Pathology (N.R., C.F-.H.), Department of Pharmacology (W.C.S.), Yale University School of Medicine, New Haven, CT; Leon H. Charney Division of Cardiology and Cell Biology Departments of Medicine, New York University School of Medicine, NY (A.C.W., A.F.-H., A.G.S., C.F-.H.); and Department of Pharmacology, Max-Plank-Institute for Heart and Lung Research, Bad Nauheim, Germany (S.O.)
| | - Stefan Offermanns
- From the Vascular Biology and Therapeutics Program (N.R., W.C.S., C.F-.H.), Integrative Cell Signaling and Neurobiology of Metabolism Program, Section of Comparative Medicine and Department of Pathology (N.R., C.F-.H.), Department of Pharmacology (W.C.S.), Yale University School of Medicine, New Haven, CT; Leon H. Charney Division of Cardiology and Cell Biology Departments of Medicine, New York University School of Medicine, NY (A.C.W., A.F.-H., A.G.S., C.F-.H.); and Department of Pharmacology, Max-Plank-Institute for Heart and Lung Research, Bad Nauheim, Germany (S.O.)
| | - William C Sessa
- From the Vascular Biology and Therapeutics Program (N.R., W.C.S., C.F-.H.), Integrative Cell Signaling and Neurobiology of Metabolism Program, Section of Comparative Medicine and Department of Pathology (N.R., C.F-.H.), Department of Pharmacology (W.C.S.), Yale University School of Medicine, New Haven, CT; Leon H. Charney Division of Cardiology and Cell Biology Departments of Medicine, New York University School of Medicine, NY (A.C.W., A.F.-H., A.G.S., C.F-.H.); and Department of Pharmacology, Max-Plank-Institute for Heart and Lung Research, Bad Nauheim, Germany (S.O.)
| | - Carlos Fernández-Hernando
- From the Vascular Biology and Therapeutics Program (N.R., W.C.S., C.F-.H.), Integrative Cell Signaling and Neurobiology of Metabolism Program, Section of Comparative Medicine and Department of Pathology (N.R., C.F-.H.), Department of Pharmacology (W.C.S.), Yale University School of Medicine, New Haven, CT; Leon H. Charney Division of Cardiology and Cell Biology Departments of Medicine, New York University School of Medicine, NY (A.C.W., A.F.-H., A.G.S., C.F-.H.); and Department of Pharmacology, Max-Plank-Institute for Heart and Lung Research, Bad Nauheim, Germany (S.O.).
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89
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Sturm EM, Parzmair GP, Radnai B, Frei RB, Sturm GJ, Hammer A, Schuligoi R, Lippe IT, Heinemann A. Phosphoinositide-dependent protein kinase 1 (PDK1) mediates potent inhibitory effects on eosinophils. Eur J Immunol 2015; 45:1548-59. [DOI: 10.1002/eji.201445196] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 12/11/2014] [Accepted: 01/27/2015] [Indexed: 01/07/2023]
Affiliation(s)
- Eva M. Sturm
- Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - Gerald P. Parzmair
- Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - Balázs Radnai
- Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - Robert B. Frei
- Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - Gunter J. Sturm
- Department of Dermatology and Venereology; Division of Environmental Dermatology and Venereology; Medical University of Graz; Graz Austria
| | - Astrid Hammer
- Institute of Cell Biology; Histology and Embryology; Medical University of Graz; Graz Austria
| | - Rufina Schuligoi
- Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - Irmgard Th. Lippe
- Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - Akos Heinemann
- Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
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90
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Nakayama M, Inoue T, Naito M, Nakayama K, Ohara N. Attenuation of the phosphatidylinositol 3-kinase/Akt signaling pathway by Porphyromonas gingivalis gingipains RgpA, RgpB, and Kgp. J Biol Chem 2015; 290:5190-5202. [PMID: 25564612 DOI: 10.1074/jbc.m114.591610] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Porphyromonas gingivalis is a major pathogen of periodontal diseases, including periodontitis. We have investigated the effect of P. gingivalis infection on the PI3K/Akt (protein kinase B) signaling pathway in gingival epithelial cells. Here, we found that live P. gingivalis, but not heat-killed P. gingivalis, reduced Akt phosphorylation at both Thr-308 and Ser-473, which implies a decrease in Akt activity. Actually, PI3K, which is upstream of Akt, was also inactivated by P. gingivalis. Furthermore, glycogen synthase kinase 3α/β, mammalian target of rapamycin, and Bad, which are downstream proteins in the PI3K/Akt cascade, were also dephosphorylated, a phenomenon consistent with Akt inactivation by P. gingivalis. However, these events did not require direct interaction between bacteria and host cells and were independent of P. gingivalis invasion into the cells. The use of gingipain-specific inhibitors and a gingipain-deficient P. gingivalis mutant KDP136 revealed that the gingipains and their protease activities were essential for the inactivation of PI3K and Akt. The associations between the PI3K regulatory subunit p85α and membrane proteins were disrupted by wild-type P. gingivalis. Moreover, PDK1 translocation to the plasma membrane was reduced by wild-type P. gingivalis, but not KDP136, indicating little production of phosphatidylinositol 3,4,5-triphosphate by PI3K. Therefore, it is likely that PI3K failed to transmit homeostatic extracellular stimuli to intracellular signaling pathways by gingipains. Taken together, our findings indicate that P. gingivalis attenuates the PI3K/Akt signaling pathway via the proteolytic effects of gingipains, resulting in the dysregulation of PI3K/Akt-dependent cellular functions and the destruction of epithelial barriers.
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Affiliation(s)
- Masaaki Nakayama
- From the Department of Oral Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and; the Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University, Okayama 700-8558 and
| | - Tetsuyoshi Inoue
- From the Department of Oral Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and; the Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University, Okayama 700-8558 and
| | - Mariko Naito
- the Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8588, Japan
| | - Koji Nakayama
- the Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8588, Japan
| | - Naoya Ohara
- From the Department of Oral Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and; the Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University, Okayama 700-8558 and.
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91
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Wellington KW. Understanding cancer and the anticancer activities of naphthoquinones – a review. RSC Adv 2015. [DOI: 10.1039/c4ra13547d] [Citation(s) in RCA: 200] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Naphthoquinone moieties are present in drugs such as doxorubicin which are used clinically to treat solid cancers.
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92
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Nakagawa A, Sullivan KD, Xue D. Caspase-activated phosphoinositide binding by CNT-1 promotes apoptosis by inhibiting the AKT pathway. Nat Struct Mol Biol 2014; 21:1082-90. [PMID: 25383666 PMCID: PMC4256149 DOI: 10.1038/nsmb.2915] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 10/14/2014] [Indexed: 12/22/2022]
Abstract
Inactivation of cell survival factors is a crucial step in apoptosis. The phosphoinositide 3 kinase (PI3K) and AKT signaling pathway promotes cell growth, proliferation and survival and its deregulation causes cancer. How this pathway is suppressed to promote apoptosis is poorly understood. Here we report the identification of a CED-3 caspase substrate in C. elegans, CNT-1, that upon cleavage by CED-3 during apoptosis activates an N-terminal phosphoinositide-binding fragment (tCNT-1), which translocates from cytoplasm to plasma membrane to block AKT binding to phosphatidylinositol (3,4,5)-triphosphate (PIP3), thereby disabling AKT activation and its pro-survival activity. Our findings reveal a new mechanism that negatively regulates AKT cell signaling to promote apoptosis and that may restrict cell growth and proliferation in normal cells.
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Affiliation(s)
- Akihisa Nakagawa
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Boulder, Colorado, USA
| | - Kelly D Sullivan
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Boulder, Colorado, USA
| | - Ding Xue
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Boulder, Colorado, USA
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93
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Xu K, Liu P, Wei W. mTOR signaling in tumorigenesis. Biochim Biophys Acta Rev Cancer 2014; 1846:638-54. [PMID: 25450580 DOI: 10.1016/j.bbcan.2014.10.007] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 10/23/2014] [Accepted: 10/25/2014] [Indexed: 12/25/2022]
Abstract
mTOR (the mechanistic target of rapamycin) is an atypical serine/threonine kinase involved in regulating major cellular functions including growth and proliferation. Deregulation of the mTOR signaling pathway is one of the most commonly observed pathological alterations in human cancers. To this end, oncogenic activation of the mTOR signaling pathway contributes to cancer cell growth, proliferation and survival, highlighting the potential for targeting the oncogenic mTOR pathway members as an effective anti-cancer strategy. In order to do so, a thorough understanding of the physiological roles of key mTOR signaling pathway components and upstream regulators would guide future targeted therapies. Thus, in this review, we summarize available genetic mouse models for mTORC1 and mTORC2 components, as well as characterized mTOR upstream regulators and downstream targets, and assign a potential oncogenic or tumor suppressive role for each evaluated molecule. Together, our work will not only facilitate the current understanding of mTOR biology and possible future research directions, but more importantly, provide a molecular basis for targeted therapies aiming at key oncogenic members along the mTOR signaling pathway.
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Affiliation(s)
- Kai Xu
- Department of Otolaryngology-Head and Neck Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China; Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Pengda Liu
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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94
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Cheng KK, Akasaki Y, Lecommandeur E, Lindsay RT, Murfitt S, Walsh K, Griffin JL. Metabolomic analysis of akt1-mediated muscle hypertrophy in models of diet-induced obesity and age-related fat accumulation. J Proteome Res 2014; 14:342-52. [PMID: 25231380 PMCID: PMC4286153 DOI: 10.1021/pr500756u] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Akt1
is a serine/threonine kinase that promotes cell growth and
survival. Previously, Akt1 activation in a double transgenic (DTG)
mouse model fed a high-fat/high-sucrose (HF/HS) diet was found to
promote type IIb muscle growth and to lead to a significant reduction
in obesity. Here, we have used metabolomics to examine the metabolic
perturbations in blood serum and liver and gastrocnemius tissues of
the DTG mice. Multivariate statistics highlighted consistent metabolic
changes in gastrocnemius muscle following Akt1 activation, which included
significant reductions of serine and histidine-containing dipeptides
(anserine and carnosine), in addition to increased concentrations
of phosphorylated sugars. In addition, Akt1-mediated regression in
obesity could be associated with increased glycolysis in gastrocnemius
muscle as well as increased gluconeogenesis, glycogenolysis, and ketogenesis
in the liver. In old DTG animals, Akt1 activation was found to improve
glucose metabolism and confer a beneficial effect in the regression
of age-related fat accumulation. This study identifies metabolic changes
induced by Akt1-mediated muscle growth and demonstrates a cross-talk
between distant organs that leads to a regression of fat mass. The
current findings indicate that agents that promote Akt1 induction
in muscle have utility in the regression of obesity.
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Affiliation(s)
- Kian-Kai Cheng
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge , Cambridge CB2 1GA, United Kingdom
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95
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Abstract
Akt regulates critical cellular processes including cell survival and proliferation, glucose metabolism, cell migration, cancer progression and metastasis through phosphorylation of a variety of downstream targets. The Akt pathway is one of the most prevalently hyperactivated signaling pathways in human cancer, thus, research deciphering molecular mechanisms which underlie the aberrant Akt activation has received enormous attention. The PI3K-dependent Akt serine/threonine phosphorylation by PDK1 and mTORC2 has long been thought to be the primary mechanism accounting for Akt activation. However, this regulation alone does not sufficiently explain how Akt hyperactivation can occur in tumors with normal levels of PI3K/PTEN activity. Mounting evidence demonstrates that aberrant Akt activation can be attributed to other posttranslational modifications, which include tyrosine phosphorylation, O-GlcNAcylation, as well as lysine modifications: ubiquitination, SUMOylation and acetylation. Among them, K63-linked ubiquitination has been shown to be a critical step for Akt signal activation by facilitating its membrane recruitment. Deficiency of E3 ligases responsible for growth factor-induced Akt activation leads to tumor suppression. Therefore, a comprehensive understanding of posttranslational modifications in Akt regulation will offer novel strategies for cancer therapy.
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96
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Lu J, Zhang Z, Ni Z, Shen H, Tu Z, Liu H, Lu R. QM/MM–PB/SA scoring of the interaction strength between Akt kinase and apigenin analogues. Comput Biol Chem 2014; 52:25-33. [DOI: 10.1016/j.compbiolchem.2014.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 05/20/2014] [Accepted: 07/25/2014] [Indexed: 12/11/2022]
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97
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Reed SA, Raja JS, Hoffman ML, Zinn SA, Govoni KE. Poor maternal nutrition inhibits muscle development in ovine offspring. J Anim Sci Biotechnol 2014; 5:43. [PMID: 25247074 PMCID: PMC4170199 DOI: 10.1186/2049-1891-5-43] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 09/01/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Maternal over and restricted nutrition has negative consequences on the muscle of offspring by reducing muscle fiber number and altering regulators of muscle growth. To determine if over and restricted maternal nutrition affected muscle growth and gene and protein expression in offspring, 36 pregnant ewes were fed 60%, 100% or 140% of National Research Council requirements from d 31 ± 1.3 of gestation until parturition. Lambs from control-fed (CON), restricted-fed (RES) or over-fed (OVER) ewes were necropsied within 1 d of birth (n = 18) or maintained on a control diet for 3 mo (n = 15). Semitendinosus muscle was collected for immunohistochemistry, and protein and gene expression analysis. RESULTS Compared with CON, muscle fiber cross-sectional area (CSA) increased in RES (58%) and OVER (47%) lambs at 1 d of age (P < 0.01); however at 3 mo, CSA decreased 15% and 17% compared with CON, respectively (P < 0.01). Compared with CON, muscle lipid content was increased in OVER (212.4%) and RES (92.5%) at d 1 (P < 0.0001). Muscle lipid content was increased 36.1% in OVER and decreased 23.6% in RES compared with CON at 3 mo (P < 0.0001). At d 1, myostatin mRNA abundance in whole muscle tended to be greater in OVER (P = 0.07) than CON. Follistatin mRNA abundance increased in OVER (P = 0.04) and tended to increase in RES (P = 0.06) compared with CON at d 1. However, there was no difference in myostatin or follistatin protein expression (P > 0.3). Phosphorylated Akt (ser473) was increased in RES at 3 mo compared with CON (P = 0.006). CONCLUSIONS In conclusion, maternal over and restricted nutrient intake alters muscle lipid content and growth of offspring, possibly through altered gene and protein expression.
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Affiliation(s)
- Sarah A Reed
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, USA
| | - Joseline S Raja
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, USA
| | - Maria L Hoffman
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, USA
| | - Steven A Zinn
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, USA
| | - Kristen E Govoni
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, USA
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98
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Abstract
Precise control of the balance between protein phosphorylation, catalyzed by protein kinases, and protein dephosphorylation, catalyzed by protein phosphatases, is essential for cellular homeostasis. Dysregulation of this balance leads to pathophysiological states, driving diseases such as cancer, heart disease, and diabetes. Aberrant phosphorylation of components of the pathways that control cell growth and cell survival are particularly prevalent in cancer. One of the most studied tumor suppressors in these pathways is the lipid phosphatase PTEN (phosphatase and tensin homolog deleted on chromosome ten), which dephosphorylates the lipid second messenger phosphatidylinositol 3,4,5-trisphosphate (PIP3), thus preventing activation of the oncogenic kinase AKT (v-akt murine thymoma viral oncogene homolog). In 2005, the discovery of a family of protein phosphatases whose members directly dephosphorylate and inactivate AKT introduced a new negative regulator of the phosphoinositide 3-kinase (PI3K) oncogenic pathway. Pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) isozymes comprise a novel tumor suppressor family whose two members, PHLPP1 and PHLPP2, are deleted as frequently as PTEN in cancers such as those of the prostate. PHLPP is thus a novel therapeutic target to suppress oncogenic pathways and is a potential candidate biomarker to stratify patients for the appropriate targeted therapeutics. This review discusses the role of PHLPP in terminating AKT signaling and how pharmacological intervention would impact this pathway.
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Affiliation(s)
- Alexandra C Newton
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093;
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99
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Rojas JM, Schwartz MW. Control of hepatic glucose metabolism by islet and brain. Diabetes Obes Metab 2014; 16 Suppl 1:33-40. [PMID: 25200294 PMCID: PMC4191916 DOI: 10.1111/dom.12332] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 04/18/2014] [Indexed: 12/19/2022]
Abstract
Dysregulation of hepatic glucose uptake (HGU) and inability of insulin to suppress hepatic glucose production (HGP) contribute to hyperglycaemia in patients with type 2 diabetes (T2D). Growing evidence suggests that insulin can inhibit HGP not only through a direct effect on the liver but also through a mechanism involving the brain. Yet, the notion that insulin action in the brain plays a physiological role in the control of HGP continues to be controversial. Although studies in dogs suggest that the direct hepatic effect of insulin is sufficient to explain day-to-day control of HGP, a surprising outcome has been revealed by recent studies in mice, investigating whether the direct hepatic action of insulin is necessary for normal HGP: when the hepatic insulin signalling pathway was genetically disrupted, HGP was maintained normally even in the absence of direct input from insulin. Here, we present evidence that points to a potentially important role of the brain in the physiological control of both HGU and HGP in response to input from insulin as well as other hormones and nutrients.
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Affiliation(s)
- Jennifer M. Rojas
- Diabetes and Obesity Center of Excellence, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Michael W. Schwartz
- Diabetes and Obesity Center of Excellence, Department of Medicine, University of Washington, Seattle, Washington, USA
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100
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Girardi C, James P, Zanin S, Pinna LA, Ruzzene M. Differential phosphorylation of Akt1 and Akt2 by protein kinase CK2 may account for isoform specific functions. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1865-74. [DOI: 10.1016/j.bbamcr.2014.04.020] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 03/25/2014] [Accepted: 04/17/2014] [Indexed: 10/25/2022]
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