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Zhang H, Wang Z, Li Q, Cao C, Guo Y, Chen Y. IRTKS promotes osteogenic differentiation by inhibiting PTEN phosphorylation. Biomed Pharmacother 2024; 177:116872. [PMID: 38908202 DOI: 10.1016/j.biopha.2024.116872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/27/2024] [Accepted: 06/03/2024] [Indexed: 06/24/2024] Open
Abstract
Insulin stimulates osteoblast proliferation and differentiation as an anabolic agent in bone. Insulin Receptor Tyrosine Kinase Substrate (IRTKS) is involved in insulin signaling as an adapter for insulin receptors (IR). Here, we showed that IRTKS levels were significantly decreased in bone marrow mesenchymal stem cells (BMSCs) derived from the bone marrow of patients with osteoporosis. Based on relevant experiments, we observed that IRTKS promoted the proliferation, migration, and osteoblast differentiation of BMSCs and MC3T3-E1 cells. In addition, we identified a Phosphatase and Tensin homolog deleted on chromosome 10 (PTEN) as a potential active substrate of IRTKS. We demonstrated a direct interaction between IRTKS and PTEN using co-immunoprecipitation. Subsequently, we confirmed that the SH3 domain of IRTKS directly binds to the C-terminal tail of PTEN. Further experimental results demonstrated that PTEN attenuated the promoting effects of IRTKS on the proliferation, migration, and osteoblast differentiation of BMSCs and MC3T3-E1 cells. In conclusion, this study suggests that IRTKS contributes to osteogenic differentiation by inhibiting PTEN phosphorylation and provides a potential therapeutic target for osteoporosis patients.
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Affiliation(s)
- Hengshuo Zhang
- Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong 250012, PR China; The First Clinical College of Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, PR China
| | - Ziyu Wang
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, PR China
| | - Qinghui Li
- Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong 250012, PR China; The First Clinical College of Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, PR China
| | - Congcong Cao
- Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong 250012, PR China; The First Clinical College of Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, PR China
| | - Yongyuan Guo
- Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong 250012, PR China.
| | - Yunzhen Chen
- Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong 250012, PR China.
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2
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Ivovic A, Yung JHM, Oprescu AI, Vlavcheski F, Mori Y, Rahman SMN, Ye W, Eversley JA, Wheeler MB, Woo M, Tsiani E, Giacca A. β-Cell Insulin Resistance Plays a Causal Role in Fat-Induced β-Cell Dysfunction In Vitro and In Vivo. Endocrinology 2024; 165:bqae044. [PMID: 38578954 PMCID: PMC11033845 DOI: 10.1210/endocr/bqae044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 03/27/2024] [Accepted: 04/04/2024] [Indexed: 04/07/2024]
Abstract
In the classical insulin target tissues of liver, muscle, and adipose tissue, chronically elevated levels of free fatty acids (FFA) impair insulin signaling. Insulin signaling molecules are also present in β-cells where they play a role in β-cell function. Therefore, inhibition of the insulin/insulin-like growth factor 1 pathway may be involved in fat-induced β-cell dysfunction. To address the role of β-cell insulin resistance in FFA-induced β-cell dysfunction we co-infused bisperoxovanadate (BPV) with oleate or olive oil for 48 hours in rats. BPV, a tyrosine phosphatase inhibitor, acts as an insulin mimetic and is devoid of any antioxidant effect that could prevent β-cell dysfunction, unlike most insulin sensitizers. Following fat infusion, rats either underwent hyperglycemic clamps for assessment of β-cell function in vivo or islets were isolated for ex vivo assessment of glucose-stimulated insulin secretion (GSIS). We also incubated islets with oleate or palmitate and BPV for in vitro assessment of GSIS and Akt (protein kinase B) phosphorylation. Next, mice with β-cell specific deletion of PTEN (phosphatase and tensin homolog; negative regulator of insulin signaling) and littermate controls were infused with oleate for 48 hours, followed by hyperglycemic clamps or ex vivo evaluation of GSIS. In rat experiments, BPV protected against fat-induced impairment of β-cell function in vivo, ex vivo, and in vitro. In mice, β-cell specific deletion of PTEN protected against oleate-induced β-cell dysfunction in vivo and ex vivo. These data support the hypothesis that β-cell insulin resistance plays a causal role in FFA-induced β-cell dysfunction.
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Affiliation(s)
- Aleksandar Ivovic
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Justin Hou Ming Yung
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Andrei I Oprescu
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Filip Vlavcheski
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Yusaku Mori
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Division of Diabetes, Metabolism, and Endocrinology, Anti-Glycation Research Section, Department of Medicine, Showa University School of Medicine, Shinagawa, Tokyo 142-8555, Japan
| | - S M Niazur Rahman
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Wenyue Ye
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Judith A Eversley
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Michael B Wheeler
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Minna Woo
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Toronto General Hospital Research Institute, University Health Network, University of Toronto, Toronto, ON M5G 2C4, Canada
- Division of Endocrinology, Department of Medicine, University Health Network, University of Toronto, Toronto, ON M5G 2C4, Canada
- Department of Medicine, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Banting and Best Diabetes Centre, University of Toronto, Toronto, ON M5G 2C4, Canada
| | - Evangelia Tsiani
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Adria Giacca
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Medicine, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Banting and Best Diabetes Centre, University of Toronto, Toronto, ON M5G 2C4, Canada
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3
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Kulak K, Kuska K, Colineau L, Mckay M, Maziarz K, Slaby J, Blom AM, King BC. Intracellular C3 protects β-cells from IL-1β-driven cytotoxicity via interaction with Fyn-related kinase. Proc Natl Acad Sci U S A 2024; 121:e2312621121. [PMID: 38346191 PMCID: PMC10895342 DOI: 10.1073/pnas.2312621121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 01/03/2024] [Indexed: 02/15/2024] Open
Abstract
One of the hallmarks of type 1 but also type 2 diabetes is pancreatic islet inflammation, associated with altered pancreatic islet function and structure, if unresolved. IL-1β is a proinflammatory cytokine which detrimentally affects β-cell function. In the course of diabetes, complement components, including the central complement protein C3, are deregulated. Previously, we reported high C3 expression in human pancreatic islets, with upregulation after IL-1β treatment. In the current investigation, using primary human and rodent material and CRISPR/Cas9 gene-edited β-cells deficient in C3, or producing only cytosolic C3 from a noncanonical in-frame start codon, we report a protective effect of C3 against IL-1β-induced β-cell death, that is attributed to the cytosolic fraction of C3. Further investigation revealed that intracellular C3 alleviates IL-1β-induced β-cell death, by interaction with and inhibition of Fyn-related kinase (FRK), which is involved in the response of β-cells to cytokines. Furthermore, these data were supported by increased β-cell death in vivo in a β-cell-specific C3 knockout mouse. Our data indicate that a functional, cytoprotective association exists between FRK and cytosolic C3.
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Affiliation(s)
- Klaudia Kulak
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
| | - Katarzyna Kuska
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
| | - Lucie Colineau
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
| | - Marina Mckay
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
| | - Karolina Maziarz
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
| | - Julia Slaby
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
| | - Anna M Blom
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
| | - Ben C King
- Section of Medical Protein Chemistry, Department of Translational Medicine, Lund University, Malmö 214-28, Sweden
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4
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Chen X, Zhang Z, Niu H, Tian X, Tian H, Yao W, He H, Shi H, Li C, Luo J. Goat Milk Improves Glucose Metabolism in Type 2 Diabetic Mice and Protects Pancreatic β-Cell Functions. Mol Nutr Food Res 2024; 68:e2200842. [PMID: 37990402 DOI: 10.1002/mnfr.202200842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 07/13/2023] [Indexed: 11/23/2023]
Abstract
SCOPE Consuming goat milk is known to benefit high-fat diet-fed and streptozocin (STZ)-induced diabetic rats, but the underlying mechanisms are unknown. This study is conducted to investigate the metabolic effects of a goat milk diet (a form of goat milk powder) on glucose homeostasis and pancreatic conditions in a mouse model of Type 2 diabetes mellitus (T2DM) induced by STZ. METHODS AND RESULTS T2DM mice are fed with a goat-milk-based diet containing 10.3% w/w goat milk powder for 10 weeks for investigating the in vivo effects; a β-cell line MIN6 cells are used to test the in vitro effects of digested goat milk (DGM). Goat milk diet improves the deleterious effects of STZ on fasting glucose levels and glucose tolerance, accelerates pancreatic structure recovery, and alters blood metabolites in mice. Based on the significant differences observed in metabolites, the key pathways, metabolite regulatory enzymes, metabolite molecular modules, and biochemical reactions are identified as critical integrated pathways. DGM promotes the cell activity, glucose transportation, and AKT activation in cultured STZ-treated MIN6 cells in vitro. CONCLUSIONS Goat milk diet improves glucose homeostasis and pancreatic conditions of T2DM mice, in association with improved blood metabolite profiles and activation of pancreatic AKT pathway.
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Affiliation(s)
- Xiaoying Chen
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zhifei Zhang
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Huiming Niu
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xinmiao Tian
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Huibin Tian
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Weiwei Yao
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Huanshan He
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Huaiping Shi
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Cong Li
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Jun Luo
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
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5
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Cao R, Tian H, Zhang Y, Liu G, Xu H, Rao G, Tian Y, Fu X. Signaling pathways and intervention for therapy of type 2 diabetes mellitus. MedComm (Beijing) 2023; 4:e283. [PMID: 37303813 PMCID: PMC10248034 DOI: 10.1002/mco2.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 04/18/2023] [Accepted: 04/27/2023] [Indexed: 06/13/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) represents one of the fastest growing epidemic metabolic disorders worldwide and is a strong contributor for a broad range of comorbidities, including vascular, visual, neurological, kidney, and liver diseases. Moreover, recent data suggest a mutual interplay between T2DM and Corona Virus Disease 2019 (COVID-19). T2DM is characterized by insulin resistance (IR) and pancreatic β cell dysfunction. Pioneering discoveries throughout the past few decades have established notable links between signaling pathways and T2DM pathogenesis and therapy. Importantly, a number of signaling pathways substantially control the advancement of core pathological changes in T2DM, including IR and β cell dysfunction, as well as additional pathogenic disturbances. Accordingly, an improved understanding of these signaling pathways sheds light on tractable targets and strategies for developing and repurposing critical therapies to treat T2DM and its complications. In this review, we provide a brief overview of the history of T2DM and signaling pathways, and offer a systematic update on the role and mechanism of key signaling pathways underlying the onset, development, and progression of T2DM. In this content, we also summarize current therapeutic drugs/agents associated with signaling pathways for the treatment of T2DM and its complications, and discuss some implications and directions to the future of this field.
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Affiliation(s)
- Rong Cao
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Huimin Tian
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Yu Zhang
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Geng Liu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Haixia Xu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Guocheng Rao
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Yan Tian
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Xianghui Fu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
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6
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Tu T, Alba MM, Datta AA, Hong H, Hua B, Jia Y, Khan J, Nguyen P, Niu X, Pammidimukkala P, Slarve I, Tang Q, Xu C, Zhou Y, Stiles BL. Hepatic macrophage mediated immune response in liver steatosis driven carcinogenesis. Front Oncol 2022; 12:958696. [PMID: 36276076 PMCID: PMC9581256 DOI: 10.3389/fonc.2022.958696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/17/2022] [Indexed: 12/02/2022] Open
Abstract
Obesity confers an independent risk for carcinogenesis. Classically viewed as a genetic disease, owing to the discovery of tumor suppressors and oncogenes, genetic events alone are not sufficient to explain the progression and development of cancers. Tumor development is often associated with metabolic and immunological changes. In particular, obesity is found to significantly increase the mortality rate of liver cancer. As its role is not defined, a fundamental question is whether and how metabolic changes drive the development of cancer. In this review, we will dissect the current literature demonstrating that liver lipid dysfunction is a critical component driving the progression of cancer. We will discuss the involvement of inflammation in lipid dysfunction driven liver cancer development with a focus on the involvement of liver macrophages. We will first discuss the association of steatosis with liver cancer. This will be followed with a literature summary demonstrating the importance of inflammation and particularly macrophages in the progression of liver steatosis and highlighting the evidence that macrophages and macrophage produced inflammatory mediators are critical for liver cancer development. We will then discuss the specific inflammatory mediators and their roles in steatosis driven liver cancer development. Finally, we will summarize the molecular pattern (PAMP and DAMP) as well as lipid particle signals that are involved in the activation, infiltration and reprogramming of liver macrophages. We will also discuss some of the therapies that may interfere with lipid metabolism and also affect liver cancer development.
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Affiliation(s)
- Taojian Tu
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Mario M. Alba
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Aditi A. Datta
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Handan Hong
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Brittney Hua
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Yunyi Jia
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Jared Khan
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Phillip Nguyen
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Xiatoeng Niu
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Pranav Pammidimukkala
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Ielyzaveta Slarve
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Qi Tang
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Chenxi Xu
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Yiren Zhou
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Bangyan L. Stiles
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- *Correspondence: Bangyan L. Stiles,
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7
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Gillson J, Abd El-Aziz YS, Leck LYW, Jansson PJ, Pavlakis N, Samra JS, Mittal A, Sahni S. Autophagy: A Key Player in Pancreatic Cancer Progression and a Potential Drug Target. Cancers (Basel) 2022; 14:cancers14143528. [PMID: 35884592 PMCID: PMC9315706 DOI: 10.3390/cancers14143528] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 01/18/2023] Open
Abstract
Simple Summary With the mortality rate of pancreatic cancer predicted to rise over the coming years, it is essential that effective treatment strategies are developed as soon as possible. Pancreatic cancer has always proven very difficult to treat due to its fast growing and aggressive nature. Chemotherapeutic treatment has struggled to increase the survival rate of pancreatic cancer patients due to effective chemo-resistant properties that derive from the supporting tumor microenvironment and autophagy, a vital survival pathway. This review will explore how the autophagy pathway and tumor microenvironment help to sustain tumor survival under stress and expand into a metastatic state. Due to the comprehensive understanding of the autophagy pathway, we will highlight the potential chinks in the pancreatic tumor’s armor and identify potential targets to overcome chemo-resistance in pancreatic cancer. We will also present novel autophagy inhibitors that could reduce tumor survival and how they could be most effectively conceived. Abstract Pancreatic cancer is known to have the lowest survival outcomes among all major cancers, and unfortunately, this has only been marginally improved over last four decades. The innate characteristics of pancreatic cancer include an aggressive and fast-growing nature from powerful driver mutations, a highly defensive tumor microenvironment and the upregulation of advantageous survival pathways such as autophagy. Autophagy involves targeted degradation of proteins and organelles to provide a secondary source of cellular supplies to maintain cell growth. Elevated autophagic activity in pancreatic cancer is recognized as a major survival pathway as it provides a plethora of support for tumors by supplying vital resources, maintaining tumour survival under the stressful microenvironment and promoting other pathways involved in tumour progression and metastasis. The combination of these features is unique to pancreatic cancer and present significant resistance to chemotherapeutic strategies, thus, indicating a need for further investigation into therapies targeting this crucial pathway. This review will outline the autophagy pathway and its regulation, in addition to the genetic landscape and tumor microenvironment that contribute to pancreatic cancer severity. Moreover, this review will also discuss the mechanisms of novel therapeutic strategies that inhibit autophagy and how they could be used to suppress tumor progression.
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Affiliation(s)
- Josef Gillson
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Bill Walsh Translational Cancer Research Laboratory, Kolling Institute of Medical Research, St Leonards, Sydney, NSW 2065, Australia
| | - Yomna S. Abd El-Aziz
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Bill Walsh Translational Cancer Research Laboratory, Kolling Institute of Medical Research, St Leonards, Sydney, NSW 2065, Australia
- Oral Pathology Department, Faculty of Dentistry, Tanta University, Tanta 31527, Egypt
| | - Lionel Y. W. Leck
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Bill Walsh Translational Cancer Research Laboratory, Kolling Institute of Medical Research, St Leonards, Sydney, NSW 2065, Australia
- Cancer Drug Resistance and Stem Cell Program, University of Sydney, Sydney, NSW 2006, Australia
| | - Patric J. Jansson
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Bill Walsh Translational Cancer Research Laboratory, Kolling Institute of Medical Research, St Leonards, Sydney, NSW 2065, Australia
- Cancer Drug Resistance and Stem Cell Program, University of Sydney, Sydney, NSW 2006, Australia
| | - Nick Pavlakis
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Bill Walsh Translational Cancer Research Laboratory, Kolling Institute of Medical Research, St Leonards, Sydney, NSW 2065, Australia
| | - Jaswinder S. Samra
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Upper GI Surgical Unit, Royal North Shore Hospital and North Shore Private Hospital, St Leonards, Sydney, NSW 2065, Australia
- Australian Pancreatic Centre, St Leonards, Sydney, NSW 2065, Australia
| | - Anubhav Mittal
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Upper GI Surgical Unit, Royal North Shore Hospital and North Shore Private Hospital, St Leonards, Sydney, NSW 2065, Australia
- Australian Pancreatic Centre, St Leonards, Sydney, NSW 2065, Australia
- School of Medicine, University of Notre Dame, Darlinghurst, Sydney, NSW 2010, Australia
| | - Sumit Sahni
- Faculty of Medicine and Health, University of Sydney, Camperdown, Sydney, NSW 2050, Australia; (J.G.); (Y.S.A.E.-A.); (L.Y.W.L.); (P.J.J.); (N.P.); (J.S.S.); (A.M.)
- Bill Walsh Translational Cancer Research Laboratory, Kolling Institute of Medical Research, St Leonards, Sydney, NSW 2065, Australia
- Australian Pancreatic Centre, St Leonards, Sydney, NSW 2065, Australia
- Correspondence: ; Tel.: +61-2-9926-7829
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8
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Camaya I, Donnelly S, O'Brien B. Targeting the PI3K/Akt signaling pathway in pancreatic β-cells to enhance their survival and function: An emerging therapeutic strategy for type 1 diabetes. J Diabetes 2022; 14:247-260. [PMID: 35191175 PMCID: PMC9060113 DOI: 10.1111/1753-0407.13252] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 01/11/2022] [Indexed: 12/16/2022] Open
Abstract
Type 1 diabetes (T1D) is an autoimmune disease caused by the destruction of the insulin-producing β-cells within the pancreas. Islet transplantation represents one cure; however, during islet preparation and post transplantation significant amounts of β-cell death occur. Therefore, prevention and cure of T1D is dependent upon the preservation of β-cell function and the prevention of β-cell death. Phosphoinositide 3-kinase (PI3K)/Akt signaling represents a promising therapeutic target for T1D due to its pronounced effects on cellular survival, proliferation, and metabolism. A growing amount of evidence indicates that PI3K/Akt signaling is a critical determinant of β-cell mass and function. Modulation of the PI3K/Akt pathway, directly (via the use of highly specific protein and peptide-based biologics, excretory/secretory products of parasitic worms, and complex constituents of plant extracts) or indirectly (through microRNA interactions) can regulate the β-cell processes to ultimately determine the fate of β-cell mass. An important consideration is the identification of the specific PI3K/Akt pathway modulators that enhance β-cell function and prevent β-cell death without inducing excessive β-cell proliferation, which may carry carcinogenic side effects. Among potential PI3K/Akt pathway agonists, we have identified a novel parasite-derived protein, termed FhHDM-1 (Fasciola hepatica helminth defense molecule 1), which efficiently stimulates the PI3K/Akt pathway in β-cells to enhance function and prevent death without concomitantly inducing proliferation unlike several other identified stimulators of PI3K/Akt signaling . As such, FhHDM-1 will inform the design of biologics aimed at targeting the PI3K/Akt pathway to prevent/ameliorate not only T1D but also T2D, which is now widely recognized as an inflammatory disease characterized by β-cell dysfunction and death. This review will explore the modulation of the PI3K/Akt signaling pathway as a novel strategy to enhance β-cell function and survival.
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Affiliation(s)
- Inah Camaya
- School of Life Sciences, Faculty of ScienceThe University of Technology SydneyUltimoNew South WalesAustralia
| | - Sheila Donnelly
- School of Life Sciences, Faculty of ScienceThe University of Technology SydneyUltimoNew South WalesAustralia
| | - Bronwyn O'Brien
- School of Life Sciences, Faculty of ScienceThe University of Technology SydneyUltimoNew South WalesAustralia
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9
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Aggarwal R, Peng Z, Zeng N, Silva J, He L, Chen J, Debebe A, Tu T, Alba M, Chen CY, Stiles EX, Hong H, Stiles BL. Chronic Exposure to Palmitic Acid Down-Regulates AKT in Beta-Cells through Activation of mTOR. THE AMERICAN JOURNAL OF PATHOLOGY 2022; 192:130-145. [PMID: 34619135 PMCID: PMC8759041 DOI: 10.1016/j.ajpath.2021.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 09/09/2021] [Accepted: 09/22/2021] [Indexed: 01/03/2023]
Abstract
High circulating lipids occurring in obese individuals and insulin-resistant patients are considered a contributing factor to type 2 diabetes. Exposure to high lipid concentration is proposed to both protect and damage beta-cells under different circumstances. Here, by feeding mice a high-fat diet (HFD) for 2 weeks to up to 14 months, the study showed that HFD initially causes the beta-cells to expand in population, whereas long-term exposure to HFD is associated with failure of beta-cells and the inability of animals to respond to glucose challenge. To prevent the failure of beta-cells and the development of type 2 diabetes, the molecular mechanisms that underlie this biphasic response of beta-cells to lipid exposure were explored. Using palmitic acid (PA) in cultured beta-cells and islets, the study demonstrated that chronic exposure to lipids leads to reduced viability and inhibition of cell cycle progression concurrent with down-regulation of a pro-growth/survival kinase AKT, independent of glucose. This AKT down-regulation by PA is correlated with the induction of mTOR/S6K activity. Inhibiting mTOR activity with rapamycin induced Raptor and restored AKT activity, allowing beta-cells to gain proliferation capacity that was lost after HFD exposure. In summary, a novel mechanism in which lipid exposure may cause the dipole effects on beta-cell growth was elucidated, where mTOR acts as a lipid sensor. These mechanisms can be novel targets for future therapeutic developments.
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Affiliation(s)
- Richa Aggarwal
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Zhechu Peng
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Ni Zeng
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Joshua Silva
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Lina He
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Jingyu Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Anketse Debebe
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Taojian Tu
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Mario Alba
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Chien-Yu Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Eileen X. Stiles
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Handan Hong
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Bangyan L. Stiles
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California,Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California,Address correspondence to Bangyan L. Stiles, Ph.D., Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033.
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10
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Crespo-Masip M, Pérez-Gómez A, Guzmán C, Rayego S, Doladé N, García-Carrasco A, Jover R, Valdivielso JM. PTEN Deletion in Adult Mice Induces Hypoinsulinemia With Concomitant Low Glucose Levels. Front Endocrinol (Lausanne) 2022; 13:850214. [PMID: 35282439 PMCID: PMC8914015 DOI: 10.3389/fendo.2022.850214] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 02/04/2022] [Indexed: 12/15/2022] Open
Abstract
The PI3K/AKT pathway, negatively regulated by PTEN, plays a paramount role in glucose metabolism regulation due to its activation by the insulin receptor signaling pathway. We generated a PTEN-KO mouse to evaluate the systemic effect of the overactivation of the PI3K/AKT pathway in insulin signaling and glucose homeostasis. Our results demonstrate that PTEN-KO mice show very low glucose levels in the fasted state, which poorly respond to glucose and pyruvate administration. Insulinemia decreased without alterations in pancreatic islets. Among the possible reasons, we uncover the deregulation of the expression of proximal tubule glucose transporter and consequent glycosuria. Moreover, we evidence an altered activation of hepatic gluconeogenesis-related genes. In addition, the expression of several genes related to β-oxidation showed a delayed or even absent response to fasting, suggesting that the lack of PTEN not only impairs glucose metabolism but also slows down the use of lipids as a metabolic fuel. We conclude that the inducible full PTEN-KO mice could be a good model to study the metabolic interactions between glycidic and lipidic metabolism in hypoinsulinemic hypoglycemia and that PTEN could be an important mediator in the disease and/or a potential drug target.
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Affiliation(s)
- Maria Crespo-Masip
- Vascular & Renal Translational Research Group, IRBLleida, Spain and Spanish Research Network for Renal Diseases (RedInRen. ISCIII), Lleida, Spain
| | - Aurora Pérez-Gómez
- Vascular & Renal Translational Research Group, IRBLleida, Spain and Spanish Research Network for Renal Diseases (RedInRen. ISCIII), Lleida, Spain
| | - Carla Guzmán
- Experimental Hepatology Unit, IIS Hospital La Fe, Valencia, Spain
| | - Sandra Rayego
- Vascular & Renal Translational Research Group, IRBLleida, Spain and Spanish Research Network for Renal Diseases (RedInRen. ISCIII), Lleida, Spain
| | - Nuria Doladé
- Vascular & Renal Translational Research Group, IRBLleida, Spain and Spanish Research Network for Renal Diseases (RedInRen. ISCIII), Lleida, Spain
| | - Alicia García-Carrasco
- Vascular & Renal Translational Research Group, IRBLleida, Spain and Spanish Research Network for Renal Diseases (RedInRen. ISCIII), Lleida, Spain
| | - Ramiro Jover
- Experimental Hepatology Unit, IIS Hospital La Fe, Valencia, Spain
- CIBERehd, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Instituto de Salut Carlos III, Madrid, Spain
- Department Biochemistry and Molecular Biology, University of Valencia, Valencia, Spain
| | - José Manuel Valdivielso
- Vascular & Renal Translational Research Group, IRBLleida, Spain and Spanish Research Network for Renal Diseases (RedInRen. ISCIII), Lleida, Spain
- *Correspondence: José Manuel Valdivielso,
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11
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Camaya I, Mok TY, Lund M, To J, Braidy N, Robinson MW, Santos J, O'Brien B, Donnelly S. The parasite-derived peptide FhHDM-1 activates the PI3K/Akt pathway to prevent cytokine-induced apoptosis of β-cells. J Mol Med (Berl) 2021; 99:1605-1621. [PMID: 34374810 DOI: 10.1007/s00109-021-02122-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/13/2021] [Accepted: 07/27/2021] [Indexed: 12/31/2022]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease characterised by the destruction of the insulin-producing beta (β)-cells within the pancreatic islets. We have previously identified a novel parasite-derived molecule, termed Fasciola hepatica helminth defence molecule 1 (FhHDM-1), that prevents T1D development in non-obese diabetic (NOD) mice. In this study, proteomic analyses of pancreas tissue from NOD mice suggested that FhHDM-1 activated the PI3K/Akt signalling pathway, which is associated with β-cell metabolism, survival and proliferation. Consistent with this finding, FhHDM-1 preserved β-cell mass in NOD mice. Examination of the biodistribution of FhHDM-1 after intraperitoneal administration in NOD mice revealed that the parasite peptide localised to the pancreas, suggesting that it exerted a direct effect on the survival/function of β-cells. This was confirmed in vitro, as the interaction of FhHDM-1 with the NOD-derived β-cell line, NIT-1, resulted in increased levels of phosphorylated Akt, increased NADH and NADPH and reduced activity of the NAD-dependent DNA nick sensor, poly(ADP-ribose) polymerase (PARP-1). As a consequence, β-cell survival was enhanced and apoptosis was prevented in the presence of the pro-inflammatory cytokines that destroy β-cells during T1D pathogenesis. Similarly, FhHDM-1 protected primary human islets from cytokine-induced apoptosis. Importantly, while FhHDM-1 promoted β-cell survival, it did not induce proliferation. Collectively, these data indicate that FhHDM-1 has significant therapeutic applications to promote β-cell survival, which is required for T1D and T2D prevention and islet transplantation. KEY MESSAGES: FhHDM-1 preserves β-cell mass in NOD mice and prevents the development of T1D. FhHDM-1 enhances phosphorylation of Akt in mouse β-cell lines. FhHDM-1 increases levels of NADH/NADPH in mouse β-cell lines in vitro. FhHDM-1 prevents cytokine-induced cell death of mouse β-cell lines and primary human β-cells in vitro via activation of the PI3K/Akt pathway.
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Affiliation(s)
- Inah Camaya
- School of Life Sciences, Faculty of Science, the University of Technology Sydney, Ultimo, Australia
| | - Tsz Y Mok
- School of Life Sciences, Faculty of Science, the University of Technology Sydney, Ultimo, Australia
| | - Maria Lund
- School of Life Sciences, Faculty of Science, the University of Technology Sydney, Ultimo, Australia
| | - Joyce To
- School of Life Sciences, Faculty of Science, the University of Technology Sydney, Ultimo, Australia
| | - Nady Braidy
- Centre for Healthy Brain Ageing, University of New South Wales, Sydney, Randwick, Australia
| | - Mark W Robinson
- School of Biological Sciences, Queen's University, Belfast, Northern Ireland, UK
| | - Jerran Santos
- School of Life Sciences, Faculty of Science, the University of Technology Sydney, Ultimo, Australia
| | - Bronwyn O'Brien
- School of Life Sciences, Faculty of Science, the University of Technology Sydney, Ultimo, Australia
| | - Sheila Donnelly
- School of Life Sciences, Faculty of Science, the University of Technology Sydney, Ultimo, Australia.
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12
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Rui J, Deng S, Perdigoto AL, Ponath G, Kursawe R, Lawlor N, Sumida T, Levine-Ritterman M, Stitzel ML, Pitt D, Lu J, Herold KC. Tet2 Controls the Responses of β cells to Inflammation in Autoimmune Diabetes. Nat Commun 2021; 12:5074. [PMID: 34417463 PMCID: PMC8379260 DOI: 10.1038/s41467-021-25367-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/06/2021] [Indexed: 01/02/2023] Open
Abstract
β cells may participate and contribute to their own demise during Type 1 diabetes (T1D). Here we report a role of their expression of Tet2 in regulating immune killing. Tet2 is induced in murine and human β cells with inflammation but its expression is reduced in surviving β cells. Tet2-KO mice that receive WT bone marrow transplants develop insulitis but not diabetes and islet infiltrates do not eliminate β cells even though immune cells from the mice can transfer diabetes to NOD/scid recipients. Tet2-KO recipients are protected from transfer of disease by diabetogenic immune cells.Tet2-KO β cells show reduced expression of IFNγ-induced inflammatory genes that are needed to activate diabetogenic T cells. Here we show that Tet2 regulates pathologic interactions between β cells and immune cells and controls damaging inflammatory pathways. Our data suggests that eliminating TET2 in β cells may reduce activating pathologic immune cells and killing of β cells.
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Affiliation(s)
- Jinxiu Rui
- Departments of Immunobiology and Internal Medicine, Yale University, New Haven, CT, USA
| | - Songyan Deng
- Departments of Immunobiology and Internal Medicine, Yale University, New Haven, CT, USA
| | - Ana Luisa Perdigoto
- Departments of Immunobiology and Internal Medicine, Yale University, New Haven, CT, USA
| | - Gerald Ponath
- Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Romy Kursawe
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Nathan Lawlor
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Tomokazu Sumida
- Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | | | - Michael L Stitzel
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
- Department of Genetics and Genome Sciences and Institute for Systems Genomics, University of Connecticut, Farmington, CT, USA
| | - David Pitt
- Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Jun Lu
- Department of Genetics, Yale University, New Haven, CT, USA
| | - Kevan C Herold
- Departments of Immunobiology and Internal Medicine, Yale University, New Haven, CT, USA.
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13
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Chen CY, Li Y, Zeng N, He L, Zhang X, Tu T, Tang Q, Alba M, Mir S, Stiles EX, Hong H, Cadenas E, Stolz AA, Li G, Stiles BL. Inhibition of Estrogen-Related Receptor α Blocks Liver Steatosis and Steatohepatitis and Attenuates Triglyceride Biosynthesis. THE AMERICAN JOURNAL OF PATHOLOGY 2021; 191:1240-1254. [PMID: 33894178 PMCID: PMC8261472 DOI: 10.1016/j.ajpath.2021.04.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/08/2021] [Accepted: 04/12/2021] [Indexed: 01/02/2023]
Abstract
The estrogen-related receptor (ERR) family of orphan nuclear receptors are transcriptional activators for genes involved in mitochondrial bioenergetics and metabolism. The goal of this study was to explore the role of ERRα in lipid metabolism and the potential effect of inhibiting ERRα on the development of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). In the current study, three experimental mouse models: high-fat diet, high-carbohydrate diet, and a genetic model of hepatic insulin resistance where the liver hyperinsulinemia signal is mimicked via hepatic deletion of Pten (phosphatase and tensin homolog deleted on chromosome 10), the negative regulator of the insulin/phosphatidylinositol 3-kinase signaling pathway, were used. A recently developed small-molecule inhibitor for ERRα was used to demonstrate that inhibiting ERRα blocked NAFLD development induced by either high-carbohydrate diet or high-fat diet feeding. ERRα inhibition also diminished lipid accumulation and attenuated NASH development in the Pten null mice. Glycerolipid synthesis was discovered as an additional mechanism for ERRα-regulated NAFLD/NASH development and glycerophosphate acyltransferase 4 was identified as a novel transcriptional target of ERRα. In summary, these results establish ERRα as a major transcriptional regulator of lipid biosynthesis in addition to its characterized primary function as a regulator for mitochondrial function. This study recognizes ERRα as a potential target for NAFLD/NASH treatment and elucidates novel signaling pathways regulated by ERRα.
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Affiliation(s)
- Chien-Yu Chen
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Yang Li
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Ni Zeng
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Lina He
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Xinwen Zhang
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Taojian Tu
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Qi Tang
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Mario Alba
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Sabrina Mir
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Eileen X Stiles
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Handan Hong
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California
| | - Enrique Cadenas
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California; Department of Biochemistry, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Andrew A Stolz
- Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Gang Li
- Faculty of Health Sciences, University of Macau, Macau
| | - Bangyan L Stiles
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California; Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California.
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14
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Zhang Q, Liang H, Zhao X, Zheng L, Li Y, Gong J, Zhu Y, Jin Y, Yin Y. PTENε suppresses tumor metastasis through regulation of filopodia formation. EMBO J 2021; 40:e105806. [PMID: 33755220 PMCID: PMC8126949 DOI: 10.15252/embj.2020105806] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 01/03/2021] [Accepted: 02/01/2021] [Indexed: 01/16/2023] Open
Abstract
PTEN is one of the most frequently mutated genes in malignancies and acts as a powerful tumor suppressor. Tumorigenesis is involved in multiple and complex processes including initiation, invasion, and metastasis. The complexity of PTEN function is partially attributed to PTEN family members such as PTENα and PTENβ. Here, we report the identification of PTENε (also named as PTEN5), a novel N‐terminal‐extended PTEN isoform that suppresses tumor invasion and metastasis. We show that the translation of PTENε/PTEN5 is initiated from the CUG816 codon within the 5′UTR region of PTEN mRNA. PTENε/PTEN5 mainly localizes in the cell membrane and physically associates with and dephosphorylates VASP and ACTR2, which govern filopodia formation and cell motility. We found that endogenous depletion of PTENε/PTEN5 promotes filopodia formation and enhances the metastasis capacity of tumor cells. Overall, we identify a new isoform of PTEN with distinct subcellular localization and molecular function compared to the known members of the PTEN family. These findings advance our current understanding of the importance and diversity of PTEN functions.
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Affiliation(s)
- Qiaoling Zhang
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Hui Liang
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Xuyang Zhao
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Lin Zheng
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Yunqiao Li
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Jingjing Gong
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Yizhang Zhu
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Yan Jin
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
| | - Yuxin Yin
- Department of Pathology, School of Basic Medical Sciences, Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China.,Institute of Precision Medicine, Peking University Shenzhen Hospital, Shenzhen, China
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15
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Li YZ, Di Cristofano A, Woo M. Metabolic Role of PTEN in Insulin Signaling and Resistance. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a036137. [PMID: 31964643 DOI: 10.1101/cshperspect.a036137] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Phosphatase and tensin homolog (PTEN) is most prominently known for its function in tumorigenesis. However, a metabolic role of PTEN is emerging as a result of its altered expression in type 2 diabetes (T2D), which results in impaired insulin signaling and promotion of insulin resistance during the pathogenesis of T2D. PTEN functions in regulating insulin signaling across different organs have been identified. Through the use of a variety of models, such as tissue-specific knockout (KO) mice and in vitro cell cultures, PTEN's role in regulating insulin action has been elucidated across many cell types. Herein, we will review the recent advancements in the understanding of PTEN's metabolic functions in each of the tissues and cell types that contribute to regulating systemic insulin sensitivity and discuss how PTEN may represent a promising therapeutic strategy for treatment or prevention of T2D.
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Affiliation(s)
- Yu Zhe Li
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario M5G 2C4, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario M5G 2M9, Canada
| | - Antonio Di Cristofano
- Department of Developmental and Molecular Biology and Medicine (Oncology), Albert Einstein College of Medicine and Albert Einstein Cancer Center, Bronx, New York 10461, USA
| | - Minna Woo
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario M5G 2C4, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario M5G 2M9, Canada.,Department of Immunology, University of Toronto, Toronto, Ontario M5G 2M9, Canada.,Division of Endocrinology and Metabolism, Department of Medicine, University Health Network/Mount Sinai Hospital, University of Toronto, Toronto, Ontario M5G 2C4, Canada
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16
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Venniyoor A. PTEN: A Thrifty Gene That Causes Disease in Times of Plenty? Front Nutr 2020; 7:81. [PMID: 32582754 PMCID: PMC7290048 DOI: 10.3389/fnut.2020.00081] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/06/2020] [Indexed: 12/15/2022] Open
Abstract
The modern obesity epidemic with associated disorders of metabolism and cancer has been attributed to the presence of "thrifty genes". In the distant past, these genes helped the organism to improve energy efficiency and store excess energy safely as fat to survive periods of famine, but in the present day obesogenic environment, have turned detrimental. I propose PTEN as the likely gene as it has functions that span metabolism, cancer and reproduction, all of which are deranged in obesity and insulin resistance. The activity of PTEN can be calibrated in utero by availability of nutrients by the methylation arm of the epigenetic pathway. Deficiency of protein and choline has been shown to upregulate DNA methyltransferases (DNMT), especially 1 and 3a; these can then methylate promoter region of PTEN and suppress its expression. Thus, the gene is tuned like a metabolic rheostat proportional to the availability of specific nutrients, and the resultant "dose" of the protein, which sits astride and negatively regulates the insulin-PI3K/AKT/mTOR pathway, decides energy usage and proliferation. This "fixes" the metabolic capacity of the organism periconceptionally to a specific postnatal level of nutrition, but when faced with a discordant environment, leads to obesity related diseases.
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Affiliation(s)
- Ajit Venniyoor
- Department of Medical Oncology, National Oncology Centre, The Royal Hospital, Muscat, Oman
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17
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Lesch A, Backes TM, Langfermann DS, Rössler OG, Laschke MW, Thiel G. Ternary complex factor regulates pancreatic islet size and blood glucose homeostasis in transgenic mice. Pharmacol Res 2020; 159:104983. [PMID: 32504838 DOI: 10.1016/j.phrs.2020.104983] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/05/2020] [Accepted: 05/29/2020] [Indexed: 12/13/2022]
Abstract
A hallmark of diabetes mellitus is the inability of pancreatic β-cells to secrete sufficient amounts of insulin for maintaining normoglycemia. The formation of smaller islets may underlie the development of a diabetic phenotype, as a decreased β-cell mass will produce an insufficient amount of insulin. For a pharmacological intervention it is crucial to identify the proteins determining β-cell mass. Here, we identified the ternary complex factor (TCF) Elk-1 as a regulator of the size of pancreatic islets. Elk-1 mediates, together with a dimer of the serum-response factor (SRF), serum response element-regulated gene transcription. Elk-1 is activated in glucose-treated pancreatic β-cells but the biological functions of this protein in β-cells are so far unknown. Elk-1 and homologous TCF proteins are expressed in islets and insulinoma cells. Gene targeting experiments revealed that the TCF proteins show redundant activities. To solve the problem of functional redundancy of these homologous proteins, we generated conditional transgenic mice expressing a dominant-negative mutant of Elk-1 in pancreatic β-cells. The mutant competes with the wild-type TCFs for DNA and SRF-binding. Expression of the Elk-1 mutant in pancreatic β-cells resulted in the generation of significantly smaller islets and increased caspase-3 activity, indicating that apoptosis was responsible for the reduction of the pancreatic islet size. Glucose tolerance tests revealed that transgenic mice expressing the dominant-negative mutant of Elk-1 in pancreatic β-cells displayed impaired glucose tolerance. Thus, we show here for the first time that TCF controls important functions of pancreatic β-cells in vivo. Elk-1 may be considered as a new therapeutic target for the treatment of diabetes.
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Affiliation(s)
- Andrea Lesch
- Department of Medical Biochemistry and Molecular Biology, Saarland University, D-66421 Homburg, Germany
| | - Tobias M Backes
- Department of Medical Biochemistry and Molecular Biology, Saarland University, D-66421 Homburg, Germany
| | - Daniel S Langfermann
- Department of Medical Biochemistry and Molecular Biology, Saarland University, D-66421 Homburg, Germany
| | - Oliver G Rössler
- Department of Medical Biochemistry and Molecular Biology, Saarland University, D-66421 Homburg, Germany
| | - Matthias W Laschke
- Institute for Clinical and Experimental Surgery, Saarland University, D-66421, Homburg, Germany
| | - Gerald Thiel
- Department of Medical Biochemistry and Molecular Biology, Saarland University, D-66421 Homburg, Germany.
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18
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AKT1 Regulates Endoplasmic Reticulum Stress and Mediates the Adaptive Response of Pancreatic β Cells. Mol Cell Biol 2020; 40:MCB.00031-20. [PMID: 32179553 DOI: 10.1128/mcb.00031-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/12/2020] [Indexed: 12/31/2022] Open
Abstract
Isoforms of protein kinase B (also known as AKT) play important roles in mediating insulin and growth factor signals. Previous studies have suggested that the AKT2 isoform is critical for insulin-regulated glucose metabolism, while the role of the AKT1 isoform remains less clear. This study focuses on the effects of AKT1 on the adaptive response of pancreatic β cells. Using a mouse model with inducible β-cell-specific deletion of the Akt1 gene (βA1KO mice), we showed that AKT1 is involved in high-fat-diet (HFD)-induced growth and survival of β cells but is unnecessary for them to maintain a population in the absence of metabolic stress. When unchallenged, βA1KO mice presented the same metabolic profile and β-cell phenotype as the control mice with an intact Akt1 gene. When metabolic stress was induced by HFD, β cells in control mice with intact Akt1 proliferated as a compensatory mechanism for metabolic overload. Similar effects were not observed in βA1KO mice. We further demonstrated that AKT1 protein deficiency caused endoplasmic reticulum (ER) stress and potentiated β cells to undergo apoptosis. Our results revealed that AKT1 protein loss led to the induction of eukaryotic initiation factor 2 α subunit (eIF2α) signaling and ER stress markers under normal-chow-fed conditions, indicating chronic low-level ER stress. Together, these data established a role for AKT1 as a growth and survival factor for adaptive β-cell response and suggest that ER stress induction is responsible for this effect of AKT1.
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19
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Xu F, Na L, Li Y, Chen L. Roles of the PI3K/AKT/mTOR signalling pathways in neurodegenerative diseases and tumours. Cell Biosci 2020; 10:54. [PMID: 32266056 PMCID: PMC7110906 DOI: 10.1186/s13578-020-00416-0] [Citation(s) in RCA: 356] [Impact Index Per Article: 89.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 03/26/2020] [Indexed: 02/06/2023] Open
Abstract
The PI3 K/AKT/mTOR signalling pathway plays an important role in the regulation of signal transduction and biological processes such as cell proliferation, apoptosis, metabolism and angiogenesis. Compared with those of other signalling pathways, the components of the PI3K/AKT/mTOR signalling pathway are complicated. The regulatory mechanisms and biological functions of the PI3K/AKT/mTOR signalling pathway are important in many human diseases, including ischaemic brain injury, neurodegenerative diseases, and tumours. PI3K/AKT/mTOR signalling pathway inhibitors include single-component and dual inhibitors. Numerous PI3K inhibitors have exhibited good results in preclinical studies, and some have been clinically tested in haematologic malignancies and solid tumours. In this review, we briefly summarize the results of research on the PI3K/AKT/mTOR pathway and discuss the structural composition, activation, communication processes, regulatory mechanisms and biological functions of the PI3K/AKT/mTOR signalling pathway in the pathogenesis of neurodegenerative diseases and tumours.
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Affiliation(s)
- Fei Xu
- Department of Microbiology and Immunology, Shanghai University of Medicine & Health Sciences, 279 Zhouzhu Rd, Shanghai, 201318 China
- Collaborative Innovation Center of Shanghai University of Medicine & Health Sciences, Shanghai, 201318 China
| | - Lixin Na
- Collaborative Innovation Center of Shanghai University of Medicine & Health Sciences, Shanghai, 201318 China
- Department of Inspection and Quarantine, Shanghai University of Medicine & Health Sciences, Shanghai, 201318 China
| | - Yanfei Li
- Department of Inspection and Quarantine, Shanghai University of Medicine & Health Sciences, Shanghai, 201318 China
| | - Linjun Chen
- Department of Inspection and Quarantine, Shanghai University of Medicine & Health Sciences, Shanghai, 201318 China
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20
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Zhong T, Zhou J, Zhan S, Wang L, Niu L, Guo J, Li L, Zhang H. Molecular Characteristics, Phylogeny and Expression Profile of the PTEN Gene in Goats. Biochem Genet 2020; 58:399-411. [PMID: 32020391 DOI: 10.1007/s10528-020-09947-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 01/13/2020] [Indexed: 12/01/2022]
Abstract
Phosphatase and the tensin homologue deleted on chromosome ten (PTEN) has pleiotropic effects on cell growth, organ development, glucose metabolism and insulin resistance in mammals. In the present study, we investigated the molecular characteristics, phylogeny and expression profile of the PTEN gene in different tissues of Jianzhou Daer goats. In this study, eight different tissues from E90, E135 and D90 female goats were collected to quantify the expression pattern of the PTEN gene using quantitative real-time PCR (qPCR), western blotting and FISH. In addition, the dynamic expression of PTEN was also determined during the differentiation of goat precursor adipose cells. A 1212-bp fragment (accession number MG923848), encoding a 403-amino acid protein with a putative molecular weight of 47.14 kDa, was identified in Jianzhou Daer goats by reverse-transcription polymerase chain reaction (RT-PCR). The phylogenetic tree showed that caprine PTEN had a relatively close relationship with ovine PTEN and bovine PTEN. qPCR revealed that PTEN was highly expressed in the liver, lung and spleen, while the lowest expression levels were observed in muscle tissues (P < 0.05). Moreover, the expression of the PTEN gene showed a decreasing trend during the differentiation of goat precursor adipose cells. RNA in situ hybridization yielded a consistent result with the qPCR data. Indeed, low protein expression was found in psoas major muscle and longissimus dorsi muscle, as well as in kidney and liver. However, PTEN protein was expressed at the highest level in the brain. The expression levels of PTEN mRNA and protein were inconsistent with each other, possibly because of post-transcriptional regulation. The findings obtained in our study lay a foundation for further investigations examining the caprine PTEN gene in embryo and organ development.
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Affiliation(s)
- Tao Zhong
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China.
| | - Jingxuan Zhou
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Siyuan Zhan
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Linjie Wang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Lili Niu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jiazhong Guo
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Li Li
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Hongping Zhang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
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21
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Tu T, Chen J, Chen L, Stiles BL. Dual-Specific Protein and Lipid Phosphatase PTEN and Its Biological Functions. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a036301. [PMID: 31548229 DOI: 10.1101/cshperspect.a036301] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) encodes a 403-amino acid protein with an amino-terminal domain that shares sequence homology with the actin-binding protein tensin and the putative tyrosine-protein phosphatase auxilin. Crystal structure analysis of PTEN has revealed a C2 domain that binds to phospholipids in membranes and a phosphatase domain that displays dual-specific activity toward both tyrosine (Y), serine (S)/threonine (T), as well as lipid substrates in vitro. Characterized primarily as a lipid phosphatase, PTEN plays important roles in multiple cellular processes including cell growth/survival as well as metabolism.
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Affiliation(s)
- Taojian Tu
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90033, USA
| | - Jingyu Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90033, USA
| | - Lulu Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90033, USA
| | - Bangyan L Stiles
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90033, USA.,Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
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22
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Wan S, Zhang J, Chen X, Lang J, Li L, Chen F, Tian L, Meng Y, Yu X. MicroRNA-17-92 Regulates Beta-Cell Restoration After Streptozotocin Treatment. Front Endocrinol (Lausanne) 2020; 11:9. [PMID: 32038500 PMCID: PMC6989481 DOI: 10.3389/fendo.2020.00009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 01/07/2020] [Indexed: 02/05/2023] Open
Abstract
Objective: To clarify the role and mechanism of miR-17-92 cluster in islet beta-cell repair after streptozotocin intervention. Methods: Genetically engineered mice (miR-17-92βKO) and control RIP-Cre mice were intraperitoneally injected with multiple low dose streptozotocin. Body weight, random blood glucose (RBG), fasting blood glucose, and intraperitoneal glucose tolerance test (IPGTT) were monitored regularly. Mice were sacrificed for histological analysis 8 weeks later. Morphological changes of pancreas islets, quantity, quality, apoptosis, and proliferation of beta-cells were measured. Islets from four groups were isolated. MiRNA and mRNA were extracted and quantified. Results:MiR-17-92βKO mice showed dramatically elevated fasting blood glucose and impaired glucose tolerance after streptozotocin treatment in contrast to control mice, the reason of which is reduced beta-cell number and total mass resulting from reduced proliferation, enhanced apoptosis of beta-cells. Genes related to cell proliferation and insulin transcription repression were significantly elevated in miR-17-92βKO mice treated with streptozotocin. Furthermore, genes involved in DNA biosynthesis and damage repair were dramatically increased in miR-17-92βKO mice with streptozotocin treatment. Conclusion: Collectively, our results demonstrate that homozygous deletion of miR-17-92 cluster in mouse pancreatic beta-cells promotes the development of experimental diabetes, indicating that miR-17-92 cluster may be positively related to beta-cells restoration and adaptation after streptozotocin-induced damage.
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Affiliation(s)
- Shan Wan
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Jie Zhang
- Histology and Imaging Platform, Core Facility of West China Hospital, Sichuan University, Chengdu, China
| | - Xiang Chen
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Jiangli Lang
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Li Li
- Histology and Imaging Platform, Core Facility of West China Hospital, Sichuan University, Chengdu, China
| | - Fei Chen
- Histology and Imaging Platform, Core Facility of West China Hospital, Sichuan University, Chengdu, China
| | - Li Tian
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Yang Meng
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
- Department of Orthopedics, West China Hospital, Sichuan University, Chengdu, China
| | - Xijie Yu
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Xijie Yu ;
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23
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Wong C, Tang LH, Davidson C, Vosburgh E, Chen W, Foran DJ, Notterman DA, Levine AJ, Xu EY. Two well-differentiated pancreatic neuroendocrine tumor mouse models. Cell Death Differ 2019; 27:269-283. [PMID: 31160716 PMCID: PMC7206057 DOI: 10.1038/s41418-019-0355-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/26/2019] [Accepted: 05/07/2019] [Indexed: 02/08/2023] Open
Abstract
Multiple endocrine neoplasia type 1 (MEN1) is a genetic syndrome in which patients develop neuroendocrine tumors (NETs), including pancreatic neuroendocrine tumors (PanNETs). The prolonged latency of tumor development in MEN1 patients suggests a likelihood that other mutations cooperate with Men1 to induce PanNETs. We propose that Pten loss combined with Men1 loss accelerates tumorigenesis. To test this, we developed two genetically engineered mouse models (GEMMs)-MPR (Men1flox/flox Ptenflox/flox RIP-Cre) and MPM (Men1flox/flox Ptenflox/flox MIP-Cre) using the Cre-LoxP system with insulin-specific biallelic inactivation of Men1 and Pten. Cre in the MPR mouse model was driven by the transgenic rat insulin 2 promoter while in the MPM mouse model was driven by the knock-in mouse insulin 1 promoter. Both mouse models developed well-differentiated (WD) G1/G2 PanNETs at a much shorter latency than Men1 or Pten single deletion alone and exhibited histopathology of human MEN1-like tumor. The MPR model, additionally, developed pituitary neuroendocrine tumors (PitNETs) in the same mouse at a much shorter latency than Men1 or Pten single deletion alone as well. Our data also demonstrate that Pten plays a role in NE tumorigenesis in pancreas and pituitary. Treatment with the mTOR inhibitor rapamycin delayed the growth of PanNETs in both MPR and MPM mice, as well as the growth of PitNETs, resulting in prolonged survival in MPR mice. Our MPR and MPM mouse models are the first to underscore the cooperative roles of Men1 and Pten in cancer, particularly neuroendocrine cancer. The early onset of WD PanNETs mimicking the human counterpart in MPR and MPM mice at 7 weeks provides an effective platform for evaluating therapeutic opportunities for NETs through targeting the MENIN-mediated and PI3K/AKT/mTOR signaling pathways.
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Affiliation(s)
- Chung Wong
- Raymond and Beverly Sackler Foundation Laboratory, New Brunswick, NJ, 08901, USA.,Regeneron Inc., Tarrytown, NY, 10591, USA
| | - Laura H Tang
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY, 10065, USA
| | - Christian Davidson
- Department of Pathology, University of Utah, Huntsman Cancer Institute, Salt Lake City, UT, 84112, USA
| | - Evan Vosburgh
- Raymond and Beverly Sackler Foundation Laboratory, New Brunswick, NJ, 08901, USA.,Rutgers Cancer Institute of New Jersey, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08903, USA.,Department of Medicine, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08901, USA.,Department of Medicine, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Wenjin Chen
- Rutgers Cancer Institute of New Jersey, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08903, USA.,Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - David J Foran
- Rutgers Cancer Institute of New Jersey, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08903, USA.,Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Daniel A Notterman
- Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA
| | - Arnold J Levine
- School of Natural Sciences, Institute for Advanced Study, Princeton, NJ, 08540, USA
| | - Eugenia Y Xu
- Raymond and Beverly Sackler Foundation Laboratory, New Brunswick, NJ, 08901, USA. .,Rutgers Cancer Institute of New Jersey, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08903, USA. .,Department of Pediatrics, Robert Wood Johnson Medical School, Rutgers, the State University of New Jersey, New Brunswick, NJ, 08901, USA. .,Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA.
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24
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PTEN arginine methylation by PRMT6 suppresses PI3K-AKT signaling and modulates pre-mRNA splicing. Proc Natl Acad Sci U S A 2019; 116:6868-6877. [PMID: 30886105 DOI: 10.1073/pnas.1811028116] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Arginine methylation is a ubiquitous posttranslational modification that regulates critical cellular processes including signal transduction and pre-mRNA splicing. Here, we report that the tumor-suppressor PTEN is methylated by protein arginine methyltransferase 6 (PRMT6). Mass-spectrometry analysis reveals that PTEN is dimethylated at arginine 159 (R159). We found that PTEN is mutated at R159 in cancers, and the PTEN mutant R159K loses its capability to inhibit the PI3K-AKT cascade. Furthermore, PRMT6 is physically associated with PTEN, promotes asymmetrical dimethylation of PTEN, and regulates the PI3K-AKT cascade through PTEN R159 methylation. In addition, using transcriptome analyses, we found that PTEN R159 methylation is involved in modulation of pre-mRNA alternative splicing. Our results demonstrate that PTEN is functionally regulated by arginine methylation. We propose that PTEN arginine methylation modulates pre-mRNA alternative splicing and influences diverse physiologic processes.
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25
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Perna-Barrull D, Rodriguez-Fernandez S, Pujol-Autonell I, Gieras A, Ampudia-Carrasco RM, Villalba A, Glau L, Tolosa E, Vives-Pi M. Prenatal Betamethasone interferes with immune system development and alters target cells in autoimmune diabetes. Sci Rep 2019; 9:1235. [PMID: 30718757 PMCID: PMC6362293 DOI: 10.1038/s41598-018-37878-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 12/17/2018] [Indexed: 01/03/2023] Open
Abstract
Non-genetic factors are crucial in the pathogenesis of type 1 diabetes (T1D), a disease caused by autoimmunity against insulin-producing β-cells. Exposure to medications in the prenatal period may influence the immune system maturation, thus altering self-tolerance. Prenatal administration of betamethasone –a synthetic glucocorticoid given to women at risk of preterm delivery– may affect the development of T1D. It has been previously demonstrated that prenatal betamethasone administration protects offspring from T1D development in nonobese diabetic (NOD) mice. The direct effect of betamethasone on the immature and mature immune system of NOD mice and on target β-cells is analysed in this paper. In vitro, betamethasone decreased lymphocyte viability and induced maturation-resistant dendritic cells, which in turn impaired γδ T cell proliferation and decreased IL-17 production. Prenatal betamethasone exposure caused thymus hypotrophy in newborn mice as well as alterations in immune cells subsets. Furthermore, betamethasone decreased β-cell growth, reduced C-peptide secretion and altered the expression of genes related to autoimmunity, metabolism and islet mass in T1D target tissue. These results support the protection against T1D in the betamethasone-treated offspring and demonstrate that this drug alters the developing immune system and β-cells. Understanding how betamethasone generates self-tolerance could have potential clinical relevance in T1D.
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Affiliation(s)
- David Perna-Barrull
- Immunology Section, Germans Trias i Pujol Research Institute, Autonomous University of Barcelona, Badalona, Spain
| | - Silvia Rodriguez-Fernandez
- Immunology Section, Germans Trias i Pujol Research Institute, Autonomous University of Barcelona, Badalona, Spain
| | - Irma Pujol-Autonell
- Immunology Section, Germans Trias i Pujol Research Institute, Autonomous University of Barcelona, Badalona, Spain
| | - Anna Gieras
- Department of Immunology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Rosa M Ampudia-Carrasco
- Immunology Section, Germans Trias i Pujol Research Institute, Autonomous University of Barcelona, Badalona, Spain
| | - Adrian Villalba
- Immunology Section, Germans Trias i Pujol Research Institute, Autonomous University of Barcelona, Badalona, Spain
| | - Laura Glau
- Department of Immunology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Eva Tolosa
- Department of Immunology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marta Vives-Pi
- Immunology Section, Germans Trias i Pujol Research Institute, Autonomous University of Barcelona, Badalona, Spain. .,CIBERDEM, Barcelona, Spain.
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26
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Xie Y, Shi X, Sheng K, Han G, Li W, Zhao Q, Jiang B, Feng J, Li J, Gu Y. PI3K/Akt signaling transduction pathway, erythropoiesis and glycolysis in hypoxia (Review). Mol Med Rep 2018; 19:783-791. [PMID: 30535469 PMCID: PMC6323245 DOI: 10.3892/mmr.2018.9713] [Citation(s) in RCA: 179] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 09/17/2018] [Indexed: 12/13/2022] Open
Abstract
The purpose of this review is to summarize the research progress of PI3K/Akt signaling pathway in erythropoiesis and glycolysis. Phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) is activated by numerous genes and leads to protein kinase B (Akt) binding to the cell membrane, with the help of phosphoinositide-dependent kinase, in the PI3K/Akt signal transduction pathway. Threonine and serine phosphorylation contribute to Akt translocation from the cytoplasm to the nucleus and further mediates enzymatic biological effects, including those involved in cell proliferation, apoptosis inhibition, cell migration, vesicle transport and cell cancerous transformation. As a key downstream protein of the PI3K/Akt signaling pathway, hypoxia-inducible factor (HIF)-1 is closely associated with the concentration of oxygen in the environment. Maintaining stable levels of HIF-1 protein is critical under normoxic conditions; however, HIF-1 levels quickly increase under hypoxic conditions. HIF-1α is involved in the acute hypoxic response associated with erythropoietin, whereas HIF-2α is associated with the response to chronic hypoxia. Furthermore, PI3K/Akt can reduce the synthesis of glycogen and increase glycolysis. Inhibition of glycogen synthase kinase 3β activity by phosphorylation of its N-terminal serine increases accumulation of cyclin D1, which promotes the cell cycle and improves cell proliferation through the PI3K/Akt signaling pathway. The PI3K/Akt signaling pathway is closely associated with a variety of enzymatic biological effects and glucose metabolism.
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Affiliation(s)
- Youbang Xie
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Xuefeng Shi
- Department of Respiratory Medicine, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Kuo Sheng
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Guoxiong Han
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Wenqian Li
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Qiangqiang Zhao
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Baili Jiang
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Jianming Feng
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Jianping Li
- Department of Hematology, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
| | - Yuhai Gu
- Department of Respiratory Medicine, Qinghai Provincial People's Hospital, Xining, Qinghai 810007, P.R. China
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27
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Yin L, Cai WJ, Chang XY, Li J, Zhu LY, Su XH, Yu XF, Sun K. Analysis of PTEN expression and promoter methylation in Uyghur patients with mild type 2 diabetes mellitus. Medicine (Baltimore) 2018; 97:e13513. [PMID: 30544451 PMCID: PMC6310531 DOI: 10.1097/md.0000000000013513] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Phosphatase and tension homolog deleted on chromosome 10 (PTEN) was considered as a promising target in type 2 diabetes mellitus (T2DM) because of its negative effects on insulin resistance. Alteration in DNA methylation is thought to play a role in the pathogenesis of T2DM. The aim of the present study was to quantitatively evaluate the promoter methylation of PTEN in Uyghur patients with mild T2DM. We evaluated methylation levels in 21 CpG sites from -2515 bp to -2186 bp relative to the translation initiation site in 55 cases of T2DM and 50 cases of normal glucose tolerance (NGT) using the MassARRAY spectrometry. In addition, PTEN mRNA and protein levels were measured by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blotting to determine whether DNA methylation alterations were responsible for PTEN expression. Compared with NGT groups, the PTEN mRNA expression was significantly higher in Uyghur patients with mild T2DM groups. We also showed that PTEN protein expression was upregulated in Uyghur patients with mild T2DM groups, but the level of protein kinase B (AKT) was downregulated. PTEN methylation in T2DM patients was significantly lower than that in NGT groups. In addition, 2 CpG units demonstrated a significant difference between the NGT and Uyghur patients with mild T2DM groups. Furthermore, there was a negative association between promoter methylation and PTEN expression. Together, these findings suggest that epigenetic inactivation of PTEN plays an important role in Uyghur patients with mild T2DM. The aberrant methylation of CpG sites within the PTEN promoter may serve as a potential candidate biomarker for T2DM in the Uyghur population.
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Affiliation(s)
- Liang Yin
- Department of Endocrinology and Metabolism, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technolog, Wuhan, Hubei
| | - Wei-Juan Cai
- Department of Clinical Laboratory, The First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang, China
| | | | - Jun Li
- Department of Endocrinology and Metabolism
| | | | | | - Xue-Feng Yu
- Department of Endocrinology and Metabolism, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technolog, Wuhan, Hubei
| | - Kan Sun
- Department of Endocrinology and Metabolism
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Pulido R. PTEN Inhibition in Human Disease Therapy. Molecules 2018; 23:molecules23020285. [PMID: 29385737 PMCID: PMC6017825 DOI: 10.3390/molecules23020285] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 01/26/2018] [Accepted: 01/28/2018] [Indexed: 12/19/2022] Open
Abstract
The tumor suppressor PTEN is a major homeostatic regulator, by virtue of its lipid phosphatase activity against phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3], which downregulates the PI3K/AKT/mTOR prosurvival signaling, as well as by its protein phosphatase activity towards specific protein targets. PTEN catalytic activity is crucial to control cell growth under physiologic and pathologic situations, and it impacts not only in preventing tumor cell survival and proliferation, but also in restraining several cellular regeneration processes, such as those associated with nerve injury recovery, cardiac ischemia, or wound healing. In these conditions, inhibition of PTEN catalysis is being explored as a potentially beneficial therapeutic intervention. Here, an overview of human diseases and conditions in which PTEN inhibition could be beneficial is presented, together with an update on the current status of specific small molecule inhibitors of PTEN enzymatic activity, their use in experimental models, and their limitations as research or therapeutic drugs.
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Affiliation(s)
- Rafael Pulido
- Biomarkers in Cancer Unit, Biocruces Health Research Institute, 48903 Barakaldo, Spain.
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain.
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Chen CY, Chen J, He L, Stiles BL. PTEN: Tumor Suppressor and Metabolic Regulator. Front Endocrinol (Lausanne) 2018; 9:338. [PMID: 30038596 PMCID: PMC6046409 DOI: 10.3389/fendo.2018.00338] [Citation(s) in RCA: 327] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 06/05/2018] [Indexed: 12/19/2022] Open
Abstract
Phosphatase and Tensin Homolog deleted on Chromosome 10 (PTEN) is a dual phosphatase with both protein and lipid phosphatase activities. PTEN was first discovered as a tumor suppressor with growth and survival regulatory functions. In recent years, the function of PTEN as a metabolic regulator has attracted significant attention. As the lipid phosphatase that dephosphorylates phosphatidylinositol-3, 4, 5-phosphate (PIP3), PTEN reduces the level of PIP3, a critical 2nd messenger mediating the signal of not only growth factors but also insulin. In this review, we introduced the discovery of PTEN, the PTEN-regulated canonical and nuclear signals, and PTEN regulation. We then focused on the role of PTEN and PTEN-regulated signals in metabolic regulation. This included the role of PTEN in glycolysis, gluconeogenesis, glycogen synthesis, lipid metabolism as well as mitochondrial metabolism. We also included how PTEN and PTEN regulated metabolic functions may act paradoxically toward insulin sensitivity and tumor metabolism and growth. Further understanding of how PTEN regulates metabolism and how such regulations lead to different biological outcomes is necessary for interventions targeting at the PTEN-regulated signals in either cancer or diabetes treatment.
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Affiliation(s)
- Chien-Yu Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Jingyu Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Lina He
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Bangyan L. Stiles
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- *Correspondence: Bangyan L. Stiles
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Molfino A, Alessandri F, Mosillo P, Dell'Utri D, Farcomeni A, Amabile MI, Laviano A. PTEN expression and its association with glucose control and calorie supplementation in critically ill patients. Clin Nutr 2017; 37:2186-2190. [PMID: 29154111 DOI: 10.1016/j.clnu.2017.10.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/07/2017] [Accepted: 10/28/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND & AIM Phosphatase and tensin homologue (PTEN) reduces insulin sensitivity. Since critically ill patients present insulin resistance, we aimed at assessing the role of PTEN expression on glucose homeostasis and clinical outcome in patients admitted to an intensive care unit (ICU) and receiving artificial nutrition. METHODS Observational, single-center study conducted in one ICU in Rome, Italy on adult patients hospitalized for trauma. Plasma glucose levels and its variability were recorded in patients receiving artificial nutrition. PTEN expression was measured by western blotting analysis and the associations between PTEN, plasma glucose levels and variability, and calories administered were investigated. Parametric and non-parametric tests were used, as appropriate. RESULTS Twenty consecutive patients (13 men and 7 women, mean age of 37.3 ± 12.7 years) were studied. No correlation between plasma glucose and PTEN was documented (r = -0.15, P = 0.55), neither between glycemic variability and PTEN expression (r = -0.00, P = 0.99). However, total kcal/day administered and PTEN expression significantly correlated (r = 0.56, P = 0.01). Also, patients with PTEN levels below the median received less kcal/day than those with PTEN above the median (P = 0.048). This association was more pronounced when normalized per body weight (P = 0.03) and after adjusting for the average of insulin daily administered (P = 0.02). CONCLUSIONS PTEN expression might significantly contribute to glucose homeostasis and disposal in critically ill patients receiving artificial nutrition. Larger samples are necessary to confirm our observation. CLINICAL TRIAL REGISTRY NUMBER NCT01796847 (www.clinicaltrials.gov) submitted on February 11, 2013.
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Affiliation(s)
- Alessio Molfino
- Department of Clinical Medicine, Sapienza University of Rome, Italy.
| | - Francesco Alessandri
- Department of Cardiovascular, Respiratory, Nephrology, Anesthesiology and Geriatric Sciences, Sapienza University of Rome, Italy.
| | - Paola Mosillo
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Italy.
| | - Donatella Dell'Utri
- Department of Cardiovascular, Respiratory, Nephrology, Anesthesiology and Geriatric Sciences, Sapienza University of Rome, Italy.
| | - Alessio Farcomeni
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Italy.
| | - Maria Ida Amabile
- Department of Clinical Medicine, Sapienza University of Rome, Italy.
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31
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Bollard J, Patte C, Massoma P, Goddard I, Gadot N, Benslama N, Hervieu V, Ferraro-Peyret C, Cordier-Bussat M, Scoazec JY, Roche C, Walter T, Vercherat C. Combinatorial Treatment with mTOR Inhibitors and Streptozotocin Leads to Synergistic In Vitro and In Vivo Antitumor Effects in Insulinoma Cells. Mol Cancer Ther 2017; 17:60-72. [DOI: 10.1158/1535-7163.mct-17-0325] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 09/29/2017] [Accepted: 10/12/2017] [Indexed: 11/16/2022]
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Mondal P, Prasad A, Girdhar K. Interventions to improve β-cell mass and function. ANNALES D'ENDOCRINOLOGIE 2017; 78:469-477. [PMID: 28870707 DOI: 10.1016/j.ando.2016.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 10/18/2016] [Accepted: 11/09/2016] [Indexed: 01/09/2023]
Abstract
Diabetes mellitus (T2DM) has become an epidemiologically important disease worldwide and is also becoming a great matter of concern due to the effects associated with it like: high morbidity, elevated health care cost and shortened life span. T2DM is a chronic metabolic disease characterized by insulin resistance as well as β-cell dysfunction. It is widely accepted that in the face of insulin resistance, euglycemia can be maintained by increase in pancreatic β-cell mass and insulin secretion. This compensation is largely due to enhanced secretion of insulin by the β-cell mass, which is present initially, and thereby subsequent increases in β-cell mass provide additional insulin secretion. However, the mechanism by which β-cell anatomical plasticity and functional plasticity for insulin secretion is coordinated and executed in different physiological and pathophysiological states is complex and has been poorly understood. As the incidence of T2DM continues to increase at an alarming rate, it is becoming imperative to shift the research focus towards the β-cell physiology where identification of novel pathways that influence the β-cell proliferation and/or contribute to increase insulin secretion has the potential to lead to new therapies for preventing or delaying onset of disease.
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Affiliation(s)
- Prosenjit Mondal
- School of Basic Sciences, BioX, Indian Institute of Technology, Mandi, HP 175005, India.
| | - Amit Prasad
- School of Basic Sciences, BioX, Indian Institute of Technology, Mandi, HP 175005, India
| | - Khyati Girdhar
- School of Basic Sciences, BioX, Indian Institute of Technology, Mandi, HP 175005, India
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Abstract
PURPOSE OF REVIEW Inadequate insulin-producing pancreatic β-cell mass is a key feature of both type 1 and type 2 diabetes. Efforts to regenerate β-cell mass from pancreatic precursors may thus ameliorate absolute or relative insulin deficiency, thereby improving glucose homeostasis. A clear understanding of the processes that govern the generation of new β-cells in the mature pancreas will be fundamental to success in this effort. This review discusses the current state of knowledge regarding β-cell regeneration and emphasizes recent studies of significance. RECENT FINDINGS Recent reports demonstrate regenerative potential in the adult human pancreas. Further, they build on the strong existing evidence that proliferation of preexisting β-cells is the predominant source of new β-cells in adulthood by dissecting the cell cycle machinery components and critical signaling pathways required for β-cell proliferation. Finally, β-cell trophic peptides have demonstrated preclinical potential as pharmacologic regenerative agents and may form the basis for clinical interventions in the future. SUMMARY Efforts to augment β-cell regeneration by enhancing β-cell viability and proliferation may lead to novel therapeutic approaches for type 1 and type 2 diabetes. An intimate understanding of the molecular mechanisms underlying the regulation of β-cell proliferation and survival will be fundamental to the optimization of endogenous β-cell regeneration.
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Takikawa M, Ohki R. A vicious partnership between AKT and PHLDA3 to facilitate neuroendocrine tumors. Cancer Sci 2017; 108:1101-1108. [PMID: 28295876 PMCID: PMC5480075 DOI: 10.1111/cas.13235] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/01/2017] [Accepted: 03/06/2017] [Indexed: 12/19/2022] Open
Abstract
Pancreatic neuroendocrine tumors (PanNET) are rare cancers that generally have a poor prognosis. Accurate diagnosis and proper treatment of these tumors requires a better understanding of the molecular mechanisms underlying the development of PanNET. It has been shown that the mTOR inhibitor everolimus can improve the progression‐free survival of PanNET patients, suggesting that inhibition of the PI3K‐Akt‐mTOR pathway may suppress the progression of PanNET. PHLDA3 is a novel tumor suppressor protein that inhibits Akt activation by competition for binding to PIP3. Our analysis of PanNET revealed frequent loss‐of‐heterozygosity and DNA methylation at the PHLDA3 locus, resulting in strong suppression of PHLDA3 transcription. Such alterations in the PHLDA3 gene were also frequently found in lung neuroendocrine tumors (NET), suggesting the possibility that various types of NET have in common the functional loss of the PHLDA3 gene.
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Affiliation(s)
- Masahiro Takikawa
- Division of Rare Cancer Research, National Cancer Center Research Institute, Tokyo, Japan
| | - Rieko Ohki
- Division of Rare Cancer Research, National Cancer Center Research Institute, Tokyo, Japan
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35
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DJ-1 maintains energy and glucose homeostasis by regulating the function of brown adipose tissue. Cell Discov 2017; 3:16054. [PMID: 28224045 PMCID: PMC5309696 DOI: 10.1038/celldisc.2016.54] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 12/28/2016] [Indexed: 12/12/2022] Open
Abstract
DJ-1 protein is involved in multiple physiological processes, including Parkinson’s disease. However, the role of DJ-1 in the metabolism is largely unknown. Here we found that DJ-1 maintained energy balance and glucose homeostasisvia regulating brown adipose tissue (BAT) activity. DJ-1-deficient mice reduced body mass, increased energy expenditure and improved insulin sensitivity. DJ-1 deletion also resisted high-fat-diet (HFD) induced obesity and insulin resistance. Accordingly, DJ-1 transgene triggered autonomous obesity and glucose intolerance. Further BAT transplantation experiments clarified DJ-1 regulates energy and glucose homeostasis by modulating BAT function. Mechanistically, we found that DJ-1 promoted PTEN proteasomal degradation via an E3 ligase, mind bomb-2 (Mib2), which led to Akt activation and inhibited FoxO1-dependent Ucp1 (Uncoupling protein-1) expression in BAT. Consistently, ablation of Akt1 mitigated the obesity and BAT dysfunction induced by DJ-1 transgene. These findings define a new biological role of DJ-1 protein in regulating BAT function, with an implication of the therapeutic target in the treatment of metabolic disorders.
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36
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Chen Y, Tian L, Wan S, Xie Y, Chen X, Ji X, Zhao Q, Wang C, Zhang K, Hock JM, Tian H, Yu X. MicroRNA-17-92 cluster regulates pancreatic beta-cell proliferation and adaptation. Mol Cell Endocrinol 2016; 437:213-223. [PMID: 27568466 DOI: 10.1016/j.mce.2016.08.037] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 08/22/2016] [Accepted: 08/23/2016] [Indexed: 10/21/2022]
Abstract
MiR-17-92 cluster contributes to the regulation of mammalian development, aging and tumorigenesis. The functional roles of miR-17-92 in pancreatic beta-cells are largely unknown. In this study, we found that conditional deletion of miR-17-92 in mouse pancreatic beta-cells (miR-17-92βKO) significantly reduces glucose tolerance and the first phase of insulin secretion, despite normal ad libitum fed and fasting glucose levels. Proliferation is down-regulated in pancreatic beta-cells after deleting miR-17-92. MiR-17-92βKO mice show higher phosphatase and tensin homologue (PTEN) and lower phosphorylated AKT in islets. Under high fat diet challenge for 16 weeks, miR-17-92βKO mice lose compensation and exhibit higher glucose levels, and lower insulin secretion. Collectively, these data suggest that miR-17-92 is a critical contributor to molecular mechanisms regulating glucose-stimulated insulin secretion and pancreatic beta-cell adaptation under metabolic stress.
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Affiliation(s)
- Yaxi Chen
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Li Tian
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Shan Wan
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Ying Xie
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Xiang Chen
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Xiao Ji
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Qian Zhao
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Chunyu Wang
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Kun Zhang
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Janet M Hock
- The Polis Center, Indiana University-Purdue University Indianapolis, 1200 Waterway Blvd # 100, Indianapolis, IN 46202, USA
| | - Haoming Tian
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China
| | - Xijie Yu
- Laboratory of Endocrinology and Metabolism, Department of Endocrinology, National Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 610041, PR China.
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Proteasome inhibitors, including curcumin, improve pancreatic β-cell function and insulin sensitivity in diabetic mice. Nutr Diabetes 2016; 6:e205. [PMID: 27110686 PMCID: PMC4855258 DOI: 10.1038/nutd.2016.13] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 01/05/2016] [Accepted: 03/09/2016] [Indexed: 12/22/2022] Open
Abstract
Background: Type 2 diabetes stems from obesity-associated insulin resistance, and in the genetically susceptible, concomitant pancreatic β-cell failure can occur, which further exacerbates hyperglycemia. Recent work by our group and others has shown that the natural polyphenol curcumin attenuates the development of insulin resistance and hyperglycemia in mouse models of hyperinsulinemic or compensated type 2 diabetes. Although several potential downstream molecular targets of curcumin exist, it is now recognized to be a direct inhibitor of proteasome activity. We now show that curcumin also prevents β-cell failure in a mouse model of uncompensated obesity-related insulin resistance (Leprdb/db on the Kaliss background). Results: In this instance, dietary supplementation with curcumin prevented hyperglycemia, increased insulin production and lean body mass, and prolonged lifespan. In addition, we show that short-term in vivo treatment with low dosages of two molecularly distinct proteasome inhibitors celastrol and epoxomicin reverse hyperglycemia in mice with β-cell failure by increasing insulin production and insulin sensitivity. Conclusions: These studies suggest that proteasome inhibitors may prove useful for patients with diabetes by improving both β-cell function and relieving insulin resistance.
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Mondal P, Song WJ, Li Y, Yang KS, Hussain MA. Increasing β-cell mass requires additional stimulation for adaptation to secretory demand. Mol Endocrinol 2016; 29:108-20. [PMID: 25387052 DOI: 10.1210/me.2014-1265] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is caused by relative insulin deficiency, subsequent to both reduced β-cell mass and insufficient insulin secretion, and both augmenting β-cell mass and β-cell function are therapeutic strategies for treating T2DM. However, the relative significance of increasing β-cell mass vs improving β-cell stimulus secretion coupling remains unclear. We have developed a mouse model that allows proliferation of β-cells in adult mice without affecting β-cell function by inducible expression of the positive cell cycle regulator cyclin A2 specifically in β-cells. In these mice, when kept on a standard diet, doubling of β-cell mass does not result in altered glucose tolerance or glucose-stimulated circulating insulin levels. Notably, a doubling of β-cell mass also does not confer improved glycemic control and ability of β-cells to respond to diabetogenic high-fat diet-induced glucose intolerance. However, in high-fat diet-exposed mice, an increase in endogenous β-cell mass confers increased potentiation of in vivo glucose-stimulated rise in circulating insulin in response to acute pharmacologic treatment with the incretin glucagon-like peptide-1 receptor agonist exendin-4. These observations indicate that increasing endogenous β-cell mass may not be sufficient to improve glycemic control in T2DM without additional strategies to increase β-cell stimulus secretion coupling.
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Affiliation(s)
- Prosenjit Mondal
- Departments of Medicine (M.A.H.), Pediatrics (P.M., W.-J.S., Y.L., K.S.Y., M.A.H.), and Biological Chemistry (M.A.H.), Johns Hopkins University, Baltimore, Maryland 21287
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Pulido R. PTEN: a yin-yang master regulator protein in health and disease. Methods 2016; 77-78:3-10. [PMID: 25843297 DOI: 10.1016/j.ymeth.2015.02.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 02/19/2015] [Indexed: 01/16/2023] Open
Abstract
The PTEN gene is a tumor suppressor gene frequently mutated in human tumors, which encodes a ubiquitous protein whose major activity is to act as a lipid phosphatase that counteracts the action of the oncogenic PI3K. In addition, PTEN displays protein phosphatase- and catalytically-independent activities. The physiologic control of PTEN function, and its inactivation in cancer and other human diseases, including some neurodevelopmental disorders, is upon the action of multiple regulatory mechanisms. This provides a wide spectrum of potential therapeutic approaches to reconstitute PTEN activity. By contrast, inhibition of PTEN function may be beneficial in a different group of human diseases, such as type 2 diabetes or neuroregeneration-related pathologies. This makes PTEN a functionally dual yin-yang protein with high potential in the clinics. Here, a brief overview on PTEN and its relation with human disease is presented.
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Affiliation(s)
- Rafael Pulido
- BioCruces Health Research Institute, Barakaldo, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
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Albury-Warren TM, Pandey V, Spinel LP, Masternak MM, Altomare DA. Prediabetes linked to excess glucagon in transgenic mice with pancreatic active AKT1. J Endocrinol 2016; 228:49-59. [PMID: 26487674 PMCID: PMC4803065 DOI: 10.1530/joe-15-0288] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/20/2015] [Indexed: 12/31/2022]
Abstract
Protein kinase B/AKT has three isoforms (AKT1-3) and is renowned for its central role in the regulation of cell growth and proliferation, due to its constitutive activation in various cancers. AKT2, which is highly expressed in insulin-responsive tissues, has been identified as a primary regulator of glucose metabolism as Akt2 knockout mice (Akt2(-/-)) are glucose-intolerant and insulin-resistant. However, the role of AKT1 in glucose metabolism is not as clearly defined. We previously showed that mice with myristoylated Akt1 (AKT1(Myr)) expressed through a bicistronic Pdx1-TetA and TetO-MyrAkt1 system were susceptible to islet cell carcinomas, and in this study we characterized an early onset, prediabetic phenotype. Beginning at weaning (3 weeks of age), the glucose-intolerant AKT1(Myr) mice exhibited non-fasted hyperglycemia, which progressed to fasted hyperglycemia by 5 months of age. The glucose intolerance was attributed to a fasted hyperglucagonemia, and hepatic insulin resistance detectable by reduced phosphorylation of the insulin receptor following insulin injection into the inferior vena cava. In contrast, treatment with doxycycline diet to turn off the transgene caused attenuation of the non-fasted and fasted hyperglycemia, thus affirming AKT1 hyperactivation as the trigger. Collectively, this model highlights a novel glucagon-mediated mechanism by which AKT1 hyperactivation affects glucose homeostasis and provides an avenue to better delineate the molecular mechanisms responsible for diabetes mellitus and the potential association with pancreatic cancer.
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Affiliation(s)
- Toya M Albury-Warren
- Burnett School of Biomedical SciencesCollege of Medicine, University of Central Florida, 6900 Lake Nona Boulevard, Orlando, Florida 32827, USADepartment of Head and Neck SurgeryThe Greater Poland Cancer Centre, 61-866 Poznan, Poland
| | - Veethika Pandey
- Burnett School of Biomedical SciencesCollege of Medicine, University of Central Florida, 6900 Lake Nona Boulevard, Orlando, Florida 32827, USADepartment of Head and Neck SurgeryThe Greater Poland Cancer Centre, 61-866 Poznan, Poland
| | - Lina P Spinel
- Burnett School of Biomedical SciencesCollege of Medicine, University of Central Florida, 6900 Lake Nona Boulevard, Orlando, Florida 32827, USADepartment of Head and Neck SurgeryThe Greater Poland Cancer Centre, 61-866 Poznan, Poland
| | - Michal M Masternak
- Burnett School of Biomedical SciencesCollege of Medicine, University of Central Florida, 6900 Lake Nona Boulevard, Orlando, Florida 32827, USADepartment of Head and Neck SurgeryThe Greater Poland Cancer Centre, 61-866 Poznan, Poland Burnett School of Biomedical SciencesCollege of Medicine, University of Central Florida, 6900 Lake Nona Boulevard, Orlando, Florida 32827, USADepartment of Head and Neck SurgeryThe Greater Poland Cancer Centre, 61-866 Poznan, Poland
| | - Deborah A Altomare
- Burnett School of Biomedical SciencesCollege of Medicine, University of Central Florida, 6900 Lake Nona Boulevard, Orlando, Florida 32827, USADepartment of Head and Neck SurgeryThe Greater Poland Cancer Centre, 61-866 Poznan, Poland
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Zhang X, Yin B, Zhu F, Huang G, Li H. A PTEN translational isoform has PTEN-like activity. Chin J Cancer Res 2015; 27:524-32. [PMID: 26543340 DOI: 10.3978/j.issn.1000-9604.2015.10.03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND To identify PTEN isoform and explore its potential role in tumor suppression. METHODS Western blotting, over-expression, shRNA mediated knocking-down, and bioinformatic analysis were used to identify PTEN isoform and test its effect on PI3K-Akt signaling pathway. Cell proliferation, apoptosis, and migration assays were used to test PTEN isoform's biological activities. RESULTS The PTEN isoform is about 15 kDa bigger than PTEN and its expression is dependent on PTEN status. Immunoprecipitation for PTEN isoform followed by screening with antibodies against ISG15, SUMO1/2/3, Ubiquitin, and Nedd8 showed the identified PTEN isoform is not a general proteinaceous post-translational modification. In addition, overexpression of PTEN cDNA in cells did not generate PTEN isoform whereas knocking-down of PTEN reduced the protein levels of both PTEN and PTEN isoform in a proportional manner. Analysis of PTEN DNA sequence disclosed an alternative translational starting code (CTG) upstream of canonical PTEN coding sequence. Expression of cloned PTEN isoform generated a protein with a size about 15 kDa bigger than PTEN and suppressed PI3K-Akt signaling pathway in cells. Overexpression of PTEN isoform also led to decrease in cell growth and enhanced serum starvation-and UV irradiation-induced apoptosis through activation of Caspase 3. Finally, expression of PTEN isoform inhibited cell migration in scratch assay. CONCLUSIONS PTEN isoform has PTEN-like activity and might be a new tumor suppressor.
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Affiliation(s)
- Xie Zhang
- 1 Department of Gastroenterology, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang, China ; 2 School of Medicine, Ningbo University, Ningbo 315211, Zhejiang, China ; 3 Ningbo Medical Center, 4 Minimally Invasive Abdominal Surgery, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang Province, China
| | - Bowei Yin
- 1 Department of Gastroenterology, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang, China ; 2 School of Medicine, Ningbo University, Ningbo 315211, Zhejiang, China ; 3 Ningbo Medical Center, 4 Minimally Invasive Abdominal Surgery, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang Province, China
| | - Fangfang Zhu
- 1 Department of Gastroenterology, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang, China ; 2 School of Medicine, Ningbo University, Ningbo 315211, Zhejiang, China ; 3 Ningbo Medical Center, 4 Minimally Invasive Abdominal Surgery, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang Province, China
| | - Guochang Huang
- 1 Department of Gastroenterology, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang, China ; 2 School of Medicine, Ningbo University, Ningbo 315211, Zhejiang, China ; 3 Ningbo Medical Center, 4 Minimally Invasive Abdominal Surgery, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang Province, China
| | - Hong Li
- 1 Department of Gastroenterology, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang, China ; 2 School of Medicine, Ningbo University, Ningbo 315211, Zhejiang, China ; 3 Ningbo Medical Center, 4 Minimally Invasive Abdominal Surgery, Ningbo Medical Center, LiHuiLi Hospital, Ningbo 315040, Zhejiang Province, China
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Abstract
OBJECTIVES In injury conditions, myofibroblasts are induced to lay down matrix proteins and support the repair process. In this study, we investigated the role of myofibroblasts, particularly stellate cells, in the growth and regeneration of pancreatic β cells. METHODS We used both in vitro and in vivo approaches to address whether stellate cells may promote the growth of β cells. RESULTS Our experiments demonstrated that activated stellate cells support the proliferation of β cells in vitro. In vivo, mesenchymals surrounding the pancreatic islets are activated (induced to proliferate) in the islet regeneration model of Pten null mice. These mesenchymals display markers of pancreatic stellate cells, such as desmin and to a lesser extent, smooth muscle actin α. We have shown previously that targeted β-cell deletion of Pten lead to a significant increase in total islet mass. This phenotype was accompanied by an increase in peri-islet mitotic activity, particularly in islets injured by streptozotocin, a β cell-specific toxin. CONCLUSIONS Together with the in vitro observations, our data, here, suggest that that these mesenchymal cells may support the regeneration of the islets. Identifying how the communication occurs may provide clinically relevant mechanism for inducing β-cell regeneration.
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Hoffmann A, Spengler D. Role of ZAC1 in transient neonatal diabetes mellitus and glucose metabolism. World J Biol Chem 2015; 6:95-109. [PMID: 26322169 PMCID: PMC4549774 DOI: 10.4331/wjbc.v6.i3.95] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 06/19/2015] [Accepted: 07/11/2015] [Indexed: 02/05/2023] Open
Abstract
Transient neonatal diabetes mellitus 1 (TNDM1) is a rare genetic disorder representing with severe neonatal hyperglycaemia followed by remission within one and a half year and adolescent relapse with type 2 diabetes in half of the patients. Genetic defects in TNDM1 comprise uniparental isodisomy of chromosome 6, duplication of the minimal TNDM1 locus at 6q24, or relaxation of genomically imprinted ZAC1/HYMAI. Whereas the function of HYMAI, a non-coding mRNA, is still unidentified, biochemical and molecular studies show that zinc finger protein 1 regulating apoptosis and cell cycle arrest (ZAC1) behaves as a factor with versatile transcriptional functions dependent on binding to specific GC-rich DNA motives and interconnected regulation of recruited coactivator activities. Genome-wide expression profiling enabled the isolation of a number of Zac1 target genes known to regulate different aspects of β-cell function and peripheral insulin sensitivity. Among these, upregulation of Pparγ and Tcf4 impairs insulin-secretion and β-cell proliferation. Similarly, Zac1-mediated upregulation of Socs3 may attenuate β-cell proliferation and survival by inhibition of growth factor signalling. Additionally, Zac1 directly represses Pac1 and Rasgrf1 with roles in insulin secretion and β-cell proliferation. Collectively, concerted dysregulation of these target genes could contribute to the onset and course of TNDM1. Interestingly, Zac1 overexpression in β-cells spares the effects of stimulatory G-protein signaling on insulin secretion and raises the prospect for tailored treatments in relapsed TNDM1 patients. Overall, these results suggest that progress on the molecular and cellular foundations of monogenetic forms of diabetes can advance personalized therapy in addition to deepening the understanding of insulin and glucose metabolism in general.
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Phosphatase and Tensin Homologue: Novel Regulation by Developmental Signaling. JOURNAL OF SIGNAL TRANSDUCTION 2015; 2015:282567. [PMID: 26339505 PMCID: PMC4539077 DOI: 10.1155/2015/282567] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 06/06/2015] [Accepted: 07/01/2015] [Indexed: 11/18/2022]
Abstract
Phosphatase and tensin homologue (PTEN) is a critical cell endogenous inhibitor of phosphoinositide signaling in mammalian cells. PTEN dephosphorylates phosphoinositide trisphosphate (PIP3), and by so doing PTEN has the function of negative regulation of Akt, thereby inhibiting this key intracellular signal transduction pathway. In numerous cell types, PTEN loss-of-function mutations result in unopposed Akt signaling, producing numerous effects on cells. Numerous reports exist regarding mutations in PTEN leading to unregulated Akt and human disease, most notably cancer. However, less is commonly known about nonmutational regulation of PTEN. This review focuses on an emerging literature on the regulation of PTEN at the transcriptional, posttranscriptional, translational, and posttranslational levels. Specifically, a focus is placed on the role developmental signaling pathways play in PTEN regulation; this includes insulin-like growth factor, NOTCH, transforming growth factor, bone morphogenetic protein, wnt, and hedgehog signaling. The regulation of PTEN by developmental mediators affects critical biological processes including neuronal and organ development, stem cell maintenance, cell cycle regulation, inflammation, response to hypoxia, repair and recovery, and cell death and survival. Perturbations of PTEN regulation consequently lead to human diseases such as cancer, chronic inflammatory syndromes, developmental abnormalities, diabetes, and neurodegeneration.
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Xu G, Ji C, Song G, Zhao C, Shi C, Song L, Chen L, Yang L, Huang F, Pang L, Zhang N, Zhao Y, Guo X. MiR-26b modulates insulin sensitivity in adipocytes by interrupting the PTEN/PI3K/AKT pathway. Int J Obes (Lond) 2015; 39:1523-30. [PMID: 25999046 DOI: 10.1038/ijo.2015.95] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 05/06/2015] [Accepted: 05/17/2015] [Indexed: 01/14/2023]
Abstract
BACKGROUND MicroRNAs (miRNAs) have emerged as epigenetic regulators of metabolism and energy homeostasis. There is a growing body of evidence pointing to miRNAs that have important regulatory roles in insulin sensitivity. OBJECTIVE The aim of this work was to explore the expression and mechanism of action of miR-26b in obesity-related insulin resistance (IR) in adipocytes. METHODS Quantitative real-time PCR was performed to determine miR-26b expression in obese rodent models, human obesity subjects and insulin-resistant adipocytes. We analysed the roles of miR-26b overexpression and inhibition on glucose uptake in adipocytes. Western blotting was used to detect the levels of protein molecules involved in the phosphoinositide-3-kinase (PI3K) pathway. Bioinformatics and the Dual Luciferase Assay were used to identify the target gene of miR-26b. We assessed the regulatory roles of miR-26b on the phosphatase and tensin homologue (PTEN)/PI3K/AKT pathway and the relationship between miR-26b and the metabolism of human obese subjects. RESULTS Levels of miR-26b are reduced in visceral adipose tissue (VAT) in obese rodent models, human obesity and insulin-resistant adipocytes. MiR-26b promotes insulin-stimulated glucose uptake and increases insulin-stimulated glucose transporter type 4 translocation to the plasma membrane in human mature adipocytes. MiR-26b modulates insulin-stimulated AKT activation via inhibition of its target gene, PTEN, and significantly increases insulin sensitivity via the PTEN/PI3K/AKT pathway. The expression level of miR-26b negatively correlates with increasing body mass index and homeostasis model assessment for IR in human obese subjects. CONCLUSION Decreased miR-26b expression in VAT may be involved in obesity-related IR by interrupting the PTEN/PI3K/AKT pathway.
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Affiliation(s)
- G Xu
- Department of Clinical Laboratory, The 82nd Hospital of the People's Liberation Army, Huaian, China
| | - C Ji
- Department of Children Health Care, Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Nanjing, China
| | - G Song
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - C Zhao
- Department of Clinical Laboratory, The 82nd Hospital of the People's Liberation Army, Huaian, China
| | - C Shi
- Department of Children Health Care, Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Nanjing, China
| | - L Song
- Department of Clinical Laboratory, The 82nd Hospital of the People's Liberation Army, Huaian, China
| | - L Chen
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - L Yang
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - F Huang
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - L Pang
- Institute of Pediatrics, Nanjing Medical University, Nanjing, China
| | - N Zhang
- Department of Clinical Laboratory, The 82nd Hospital of the People's Liberation Army, Huaian, China
| | - Y Zhao
- Department of Clinical Laboratory, The 82nd Hospital of the People's Liberation Army, Huaian, China
| | - X Guo
- Department of Children Health Care, Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Nanjing, China
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Shao C, Gu J, Meng X, Zheng H, Wang D. Systematic investigation into the role of intermittent high glucose in pancreatic beta-cells. Int J Clin Exp Med 2015; 8:5462-5469. [PMID: 26131124 PMCID: PMC4483841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 04/03/2015] [Indexed: 06/04/2023]
Abstract
OBJECTIVES Glucose fluctuation is suggested to be the leading cause of beta-cell damages. To determine how it induces beta-cell dysfunction, we systematically evaluated the effects of intermittent high glucose (IHG) in INS-1 rat pancreatic beta-cells on their proliferation activity, apoptosis, insulin secretion, reactive oxygen species (ROS), intracellular concentration of Ca(2+) ([Ca(2+)]i), and the PTEN expression as well as AKT phosphorylation. METHODS Prior to the examinations, INS-1 cells were treated with normal glucose (NG, 11.1 mmol/L), sustained high glucose (SHG, 33 mmol/L), IHG (switching per 12 h in 11.1 mmol/l or 33 mmol/L), NG+α-lipoic acid (LA, pretreated with LA 12 h before exposure to NG), SHG+LA (pretreated with LA 12 h before being exposed to 33.3 mmol/L glucose) and IHG+LA (pretreated with LA 12 h before being cultured with IHG). The cells in each group were cultured with indicated concentrations of glucose for 3 days. The evaluations were carried out on the cell viability, apoptosis rate, insulin secretion, [Ca(2+)]i, ROS and the expressions of PTEN and p-AKT. RESULTS The current study determined that IHG induces more apoptosis and significant increases of [Ca(2+)]i and intracellular ROS levels, compared to SHG and NG treatments to INS-1 cells. Moreover, IHG leads to more than 20% decrease on cell viability and over 50% reduction on insulin secretion (from 5.48±0.79 mIU/L to 2.51±0.58 mIU/L). The negative regulation of IHG on insulin signaling in beta-cells is identified via western blot analysis with results of the elevated expression of PTEN and lowered phosphorylation levels of AKT post IHG treatment. While the pretreatment of the antioxidant LA can significantly suppress the above responses induced by high glucose treatment. CONCLUSIONS This study demonstrated that IHG plays a detrimental role in the viability, expansion, and function of beta-cells. IHG could be more harmful to the INS-1 cells than the SHG treatment. The rate increase of apoptosis in beta-cells could be caused by the suppressed insulin signaling, which is resulted from the raised ROS level by abnormal glucose treatments. Undergoing oxidative stress induced by high glucose treatments, including SHG and IHG, might be an important player in mediating the injury process to beta-cells, concluded from the beneficial rescue by the antioxidant LA treatment.
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Affiliation(s)
- Chen Shao
- Department of Geriatrics and Endocrinology, The First Affiliated Hospital of China Medical UniversityChina
| | - Jianqiu Gu
- Department of Endocrinology, The First Affiliated Hospital of China Medical UniversityChina
| | - Xin Meng
- Department of Endocrinology, The First Affiliated Hospital of China Medical UniversityChina
| | - Hongzhi Zheng
- Department of Geriatrics and Endocrinology, The First Affiliated Hospital of China Medical UniversityChina
| | - Difei Wang
- Department of Geriatrics and Endocrinology, The First Affiliated Hospital of China Medical UniversityChina
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Bridges D, Saltiel AR. Phosphoinositides: Key modulators of energy metabolism. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:857-66. [PMID: 25463477 DOI: 10.1016/j.bbalip.2014.11.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 10/31/2014] [Accepted: 11/10/2014] [Indexed: 12/19/2022]
Abstract
Phosphoinositides are key players in many trafficking and signaling pathways. Recent advances regarding the synthesis, location and functions of these lipids have dramatically improved our understanding of how and when these lipids are generated and what their roles are in animal physiology. In particular, phosphoinositides play a central role in insulin signaling, and manipulation of PtdIns(3,4,5)P₃levels in particular, may be an important potential therapeutic target for the alleviation of insulin resistance associated with obesity and the metabolic syndrome. In this article we review the metabolism, regulation and functional roles of phosphoinositides in insulin signaling and the regulation of energy metabolism. This article is part of a Special Issue entitled Phosphoinositides.
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Affiliation(s)
- Dave Bridges
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, TN, USA; Children's Foundation Research Institute, Le Bonheur Children's Hospital, Memphis, TN, USA.
| | - Alan R Saltiel
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
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Kitagishi Y, Nakanishi A, Minami A, Asai Y, Yasui M, Iwaizako A, Suzuki M, Ono Y, Ogura Y, Matsuda S. Certain Diet and Lifestyle May Contribute to Islet β-cells Protection in Type-2 Diabetes via the Modulation of Cellular PI3K/AKT Pathway. Open Biochem J 2014; 8:74-82. [PMID: 25400709 PMCID: PMC4231374 DOI: 10.2174/1874091x01408010074] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 08/13/2014] [Accepted: 08/18/2014] [Indexed: 12/18/2022] Open
Abstract
PI3K/AKT pathway has been shown to play a pivotal role on islet β-cell protection, enhancing β-cell survival by stimulating cell proliferation and inhibiting cell apoptosis. Accordingly, this pathway appears to be crucial in type-2 diabetes. Understanding the regulations of this pathway may provide a better efficacy of new therapeutic approaches. In this review, we summarize advances on the involvement of the PI3K/AKT pathway in hypothetical intra-cellular signaling of islet β-cells. As recent findings may show the nutritional regulation of the survival pathway in the islet β-cells through activation of the PI3K/AKT pathway, we also review studies on the features of several diets, correlated lifestyle, and its signaling pathway involved in type-2 diabetes. The molecular mechanisms contributing to the disease are the subject of considerable investigation, as a better understanding of the pathogenesis will lead to novel therapies against a condition of the disease.
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Affiliation(s)
- Yasuko Kitagishi
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Atsuko Nakanishi
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Akari Minami
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Yurina Asai
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Mai Yasui
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Akiko Iwaizako
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Miho Suzuki
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Yuna Ono
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Yasunori Ogura
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
| | - Satoru Matsuda
- Department of Food Science and Nutrition, Nara Women's University, Kita-Uoya Nishimachi, Nara 630-8506, Japan
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Coque E, Raoul C, Bowerman M. ROCK inhibition as a therapy for spinal muscular atrophy: understanding the repercussions on multiple cellular targets. Front Neurosci 2014; 8:271. [PMID: 25221469 PMCID: PMC4148024 DOI: 10.3389/fnins.2014.00271] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 08/11/2014] [Indexed: 12/28/2022] Open
Abstract
Spinal muscular atrophy (SMA) is the most common genetic disease causing infant death, due to an extended loss of motoneurons. This neuromuscular disorder results from deletions and/or mutations within the Survival Motor Neuron 1 (SMN1) gene, leading to a pathological decreased expression of functional full-length SMN protein. Emerging studies suggest that the small GTPase RhoA and its major downstream effector Rho kinase (ROCK), which both play an instrumental role in cytoskeleton organization, contribute to the pathology of motoneuron diseases. Indeed, an enhanced activation of RhoA and ROCK has been reported in the spinal cord of an SMA mouse model. Moreover, the treatment of SMA mice with ROCK inhibitors leads to an increased lifespan as well as improved skeletal muscle and neuromuscular junction pathology, without preventing motoneuron degeneration. Although motoneurons are the primary target in SMA, an increasing number of reports show that other cell types inside and outside the central nervous system contribute to SMA pathogenesis. As administration of ROCK inhibitors to SMA mice was systemic, the improvement in survival and phenotype could therefore be attributed to specific effects on motoneurons and/or on other non-neuronal cell types. In the present review, we will present the various roles of the RhoA/ROCK pathway in several SMA cellular targets including neurons, myoblasts, glial cells, cardiomyocytes and pancreatic cells as well as discuss how ROCK inhibition may ameliorate their health and function. It is most likely a concerted influence of ROCK modulation on all these cell types that ultimately lead to the observed benefits of pharmacological ROCK inhibition in SMA mice.
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Affiliation(s)
- Emmanuelle Coque
- The Institute for Neurosciences of Montpellier, Saint Eloi Hospital, Institut National de la Santé et de la Recherche Médicale UMR1051 Montpellier, France ; Université de Montpellier 1 and 2 Montpellier, France
| | - Cédric Raoul
- The Institute for Neurosciences of Montpellier, Saint Eloi Hospital, Institut National de la Santé et de la Recherche Médicale UMR1051 Montpellier, France ; Université de Montpellier 1 and 2 Montpellier, France
| | - Mélissa Bowerman
- The Institute for Neurosciences of Montpellier, Saint Eloi Hospital, Institut National de la Santé et de la Recherche Médicale UMR1051 Montpellier, France ; Université de Montpellier 1 and 2 Montpellier, France
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Jonatan D, Spence JR, Method AM, Kofron M, Sinagoga K, Haataja L, Arvan P, Deutsch GH, Wells JM. Sox17 regulates insulin secretion in the normal and pathologic mouse β cell. PLoS One 2014; 9:e104675. [PMID: 25144761 PMCID: PMC4140688 DOI: 10.1371/journal.pone.0104675] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 07/16/2014] [Indexed: 02/06/2023] Open
Abstract
SOX17 is a key transcriptional regulator that can act by regulating other transcription factors including HNF1β and FOXA2, which are known to regulate postnatal β cell function. Given this, we investigated the role of SOX17 in the developing and postnatal pancreas and found a novel role for SOX17 in regulating insulin secretion. Deletion of the Sox17 gene in the pancreas (Sox17-paLOF) had no observable impact on pancreas development. However, Sox17-paLOF mice had higher islet proinsulin protein content, abnormal trafficking of proinsulin, and dilated secretory organelles suggesting that Sox17-paLOF adult mice are prediabetic. Consistant with this, Sox17-paLOF mice were more susceptible to aged-related and high fat diet-induced hyperglycemia and diabetes. Overexpression of Sox17 in mature β cells using Ins2-rtTA driver mice resulted in precocious secretion of proinsulin. Transcriptionally, SOX17 appears to broadly regulate secretory networks since a 24-hour pulse of SOX17 expression resulted in global transcriptional changes in factors that regulate hormone transport and secretion. Lastly, transient SOX17 overexpression was able to reverse the insulin secretory defects observed in MODY4 animals and restored euglycemia. Together, these data demonstrate a critical new role for SOX17 in regulating insulin trafficking and secretion and that modulation of Sox17-regulated pathways might be used therapeutically to improve cell function in the context of diabetes.
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Affiliation(s)
- Diva Jonatan
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States of America
| | - Jason R. Spence
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan Medical School, Ann Arbor, MI, United States of America
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, United States of America
- Center for Organogenesis, University of Michigan Medical School, Ann Arbor, MI, United States of America
| | - Anna M. Method
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States of America
| | - Matthew Kofron
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States of America
| | - Katie Sinagoga
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States of America
| | - Leena Haataja
- Division of Metabolism, Endocrinology, and Diabetes, University of Michigan Medical School, Ann Arbor, MI, United States of America
| | - Peter Arvan
- Division of Metabolism, Endocrinology, and Diabetes, University of Michigan Medical School, Ann Arbor, MI, United States of America
| | - Gail H. Deutsch
- Seattle Children’s Hospital, Seattle, WA, United States of America
| | - James M. Wells
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States of America
- Division of Endocrinology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States of America
- * E-mail:
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