Molecular mechanisms of impaired glucose transport in insulin resistance
Lead Research Organisation:
University of Cambridge
Department Name: Institute of Metabolic Science
Abstract
Type 2 diabetes represents one of the major worldwide health challenges, with more than 400 million people diagnosed. Insulin resistance, a condition where the hormone insulin is no longer able to efficiently control blood glucose levels, is a primary risk factor for the development of type 2 diabetes. In addition, insulin resistance is also linked to a number of other chronic diseases including cardiovascular disease, some cancers and neurodegenerative disorders. Therefore, treatments to overcome insulin resistance would provide new therapeutic options for type 2 diabetes and could help reduce the burden of other insulin-resistance associated diseases.
Insulin lowers blood glucose levels, in part, by increasing glucose transport into fat and muscle tissue where it can be utilised or stored. One of the underlying causes of insulin resistance is a defect in the transport of glucose from the blood into these tissues. The processes within fat and muscle cells that are required for insulin to increase glucose transport in healthy individuals is well known. However, is not known how or which of these processes are impaired in insulin resistance. The aim of my fellowship proposal is to address this gap in knowledge by leading studies to identify the reason that the transport of glucose into fat and muscle tissue is disrupted in insulin resistance.
The longer-term goal of my work is to use this information to identify rational ways to combat insulin resistance. Improving or restoring glucose transport into fat and muscle tissues to treat insulin resistance will have two major implications for human health. Firstly, this will address a current gap in treatment options for type 2 diabetes since there are no current medications that directly target glucose transport. Secondly, since insulin resistance is now linked to a several other chronic diseases, new therapies to overcome insulin resistance may have significant implications beyond type 2 diabetes.
Insulin lowers blood glucose levels, in part, by increasing glucose transport into fat and muscle tissue where it can be utilised or stored. One of the underlying causes of insulin resistance is a defect in the transport of glucose from the blood into these tissues. The processes within fat and muscle cells that are required for insulin to increase glucose transport in healthy individuals is well known. However, is not known how or which of these processes are impaired in insulin resistance. The aim of my fellowship proposal is to address this gap in knowledge by leading studies to identify the reason that the transport of glucose into fat and muscle tissue is disrupted in insulin resistance.
The longer-term goal of my work is to use this information to identify rational ways to combat insulin resistance. Improving or restoring glucose transport into fat and muscle tissues to treat insulin resistance will have two major implications for human health. Firstly, this will address a current gap in treatment options for type 2 diabetes since there are no current medications that directly target glucose transport. Secondly, since insulin resistance is now linked to a several other chronic diseases, new therapies to overcome insulin resistance may have significant implications beyond type 2 diabetes.
Technical Summary
Insulin resistance, a condition where the hormone insulin no longer efficiently lowers blood glucose, is a risk factor for the development of type 2 diabetes, and is also linked to development of cardiovascular disease, some cancers and neurodegenerative diseases. Insulin promotes glucose uptake into adipose and muscle tissue through the redistribution of the glucose transporter GLUT4 from intracellular stores to the cell surface. This process is defective in insulin resistance. The overall aim of my fellowship is reveal the molecular mechanisms for impaired insulin-stimulated GLUT4 trafficking in insulin resistance. This comprises three specific aims. First, I will use proteomics and develop a high-throughput screening platform to find changes in protein localisation and/or protein expression that contribute to impaired GLUT4 trafficking in insulin resistance. Second, I will use microscopy techniques and trafficking assays to study the how the protein TRARG1, a recently identified regulator of GLUT4 trafficking, controls GLUT4 trafficking and whether impaired in signalling to TRARG1 plays a role in insulin resistance. Finally, I will follow up on my recent work that supports a key role for reactive oxygen species in mitochondria in insulin resistance by using phospho- and redox proteomics to map the pathway that connects mitochondrial reactive oxygen species to impaired GLUT4 trafficking in the cytosol. These studies have potential to reveal new information on how insulin regulates GLUT4 trafficking in health, and how this process becomes defective in insulin resistance.
These studies may reveal rational therapeutic options for correcting glucose transport in insulin resistance. This is significant since there are currently no medications for type 2 diabetics that target glucose transport to aid glycaemic control. In the longer term, such medications may help alleviate the development of type 2 diabetes and burden of other insulin resistance-associated disorders.
These studies may reveal rational therapeutic options for correcting glucose transport in insulin resistance. This is significant since there are currently no medications for type 2 diabetics that target glucose transport to aid glycaemic control. In the longer term, such medications may help alleviate the development of type 2 diabetes and burden of other insulin resistance-associated disorders.
Planned Impact
The following groups will benefit from my research programme and activities:
- Life sciences research community
- Clinicians and patients
- Pharmaceutical industry and life sciences companies
- General public (incl. school children)
- Research group
Life sciences research community
As described in more detail in the academic beneficiaries section, the research findings and method development as part of this project will benefit academics in a number of life sciences fields.
Clinicians and patients
The overall goal of my project is to increase our understanding of the causes of insulin resistance and metabolic disease to find new ways to improve metabolic health. While insulin resistance now appears to be a risk factor for a range of diseases, it is most commonly associated with type 2 diabetes. It is known that the efficacy of drugs (e.g metformin) to help type 2 diabetics control their blood glucose varies considerably between patients. In addition, there are currently no therapeutic options for type 2 diabetics that directly improve glucose uptake into muscle or adipose tissue, where my research is focused. Therefore, using the knowledge gathered from my studies to find new therapies to improve insulin action will improve options for clinicians, giving them a greater chance to find a combination of drugs that help each patient to control their blood glucose, and so improve patients' quality of life. While this impact will not be realised during my fellowship, this represents the major long-term impact of my proposed work.
Pharmaceutical industry and life sciences companies
This project has the potential to reveal new insight into how to improve insulin sensitivity or overcome insulin resistance by correcting/increasing insulin-stimulated glucose transport. Such therapies would also benefit those with type 2 diabetes. With > 3 million people diagnosed with type 2 diabetes in the UK in 2017 and >400 million worldwide in 2014, these findings will be of interest to the pharmaceutical industry and may attract R&D investment. In addition, during this fellowship I will generate technologies (e.g. high-throughput screen for regulators of GLUT4) and reagents (e.g. phospho-specific antibodies) that may be of commercial interest to either the pharmaceutical industry or life sciences companies.
General public (incl. school children)
This fellowship will provide me with the opportunity to engage with the general public to increase their knowledge about metabolic research and the importance of metabolic health, and to inspire students to consider medical research as a career option.
Research group
Studies within this proposal will form the basis of the early post-doctoral career or PhD studies of post-doctoral researchers and students recruited to my future group. My proposed studies address key questions and use innovative technologies, both of which will provide the best opportunity for post-doctoral researchers and students to develop their skillsets and generate data for high impact publications.
- Life sciences research community
- Clinicians and patients
- Pharmaceutical industry and life sciences companies
- General public (incl. school children)
- Research group
Life sciences research community
As described in more detail in the academic beneficiaries section, the research findings and method development as part of this project will benefit academics in a number of life sciences fields.
Clinicians and patients
The overall goal of my project is to increase our understanding of the causes of insulin resistance and metabolic disease to find new ways to improve metabolic health. While insulin resistance now appears to be a risk factor for a range of diseases, it is most commonly associated with type 2 diabetes. It is known that the efficacy of drugs (e.g metformin) to help type 2 diabetics control their blood glucose varies considerably between patients. In addition, there are currently no therapeutic options for type 2 diabetics that directly improve glucose uptake into muscle or adipose tissue, where my research is focused. Therefore, using the knowledge gathered from my studies to find new therapies to improve insulin action will improve options for clinicians, giving them a greater chance to find a combination of drugs that help each patient to control their blood glucose, and so improve patients' quality of life. While this impact will not be realised during my fellowship, this represents the major long-term impact of my proposed work.
Pharmaceutical industry and life sciences companies
This project has the potential to reveal new insight into how to improve insulin sensitivity or overcome insulin resistance by correcting/increasing insulin-stimulated glucose transport. Such therapies would also benefit those with type 2 diabetes. With > 3 million people diagnosed with type 2 diabetes in the UK in 2017 and >400 million worldwide in 2014, these findings will be of interest to the pharmaceutical industry and may attract R&D investment. In addition, during this fellowship I will generate technologies (e.g. high-throughput screen for regulators of GLUT4) and reagents (e.g. phospho-specific antibodies) that may be of commercial interest to either the pharmaceutical industry or life sciences companies.
General public (incl. school children)
This fellowship will provide me with the opportunity to engage with the general public to increase their knowledge about metabolic research and the importance of metabolic health, and to inspire students to consider medical research as a career option.
Research group
Studies within this proposal will form the basis of the early post-doctoral career or PhD studies of post-doctoral researchers and students recruited to my future group. My proposed studies address key questions and use innovative technologies, both of which will provide the best opportunity for post-doctoral researchers and students to develop their skillsets and generate data for high impact publications.
Organisations
- University of Cambridge (Fellow, Lead Research Organisation)
- AstraZeneca (Collaboration)
- Francis Crick Institute (Collaboration)
- University of Cologne (Collaboration)
- University College London (Collaboration)
- University of Toulouse (Collaboration)
- German Institute for Nutrition Research Potsdam Rehbrücke (Collaboration)
- UNIVERSITY OF CAMBRIDGE (Collaboration)
- Helmholtz Association of German Research Centres (Collaboration)
- UNIVERSITY OF SYDNEY (Collaboration)
- KING'S COLLEGE LONDON (Collaboration)
Publications
Ayer A
(2022)
The role of mitochondrial reactive oxygen species in insulin resistance.
in Free radical biology & medicine
Calejman CM
(2022)
Integrating adipocyte insulin signaling and metabolism in the multi-omics era.
in Trends in biochemical sciences
Diaz-Vegas A
(2023)
A high-content endogenous GLUT4 trafficking assay reveals new aspects of adipocyte biology.
in Life science alliance
Duan X
(2022)
Trafficking regulator of GLUT4-1 (TRARG1) is a GSK3 substrate.
in The Biochemical journal
Fazakerley D
(2022)
GLUT4 On the move.
Description | A physiological culture system to improve translation in metabolic research |
Amount | £95,000 (GBP) |
Organisation | Medical Research Council (MRC) |
Sector | Public |
Country | United Kingdom |
Start | 02/2021 |
End | 04/2021 |
Description | Cambridge Africa ALBORADA Research Fund |
Amount | £10,000 (GBP) |
Organisation | University of Cambridge |
Sector | Academic/University |
Country | United Kingdom |
Start | 02/2024 |
End | 02/2025 |
Description | Isaac Newton Trust / Wellcome Trust ISSF / University of Cambridge Joint Research Grants Scheme |
Amount | £75,000 (GBP) |
Organisation | University of Cambridge |
Sector | Academic/University |
Country | United Kingdom |
Start | 03/2021 |
End | 10/2022 |
Description | Novo Nordisk ValidatioNN Grant |
Amount | € 50,000 (EUR) |
Organisation | Novo Nordisk |
Sector | Private |
Country | Denmark |
Start | 08/2023 |
End | 09/2024 |
Title | Combined siRNA knockdown in mature adipocytes and assay for insulin action using high content imaging |
Description | Combined siRNA knockdown in mature adipocytes and assay for insulin action using high content imaging. We assay surface GLUT$ as a measure of insulin-stimulated GLUT4 translcoation. |
Type Of Material | Technology assay or reagent |
Year Produced | 2019 |
Provided To Others? | No |
Impact | This platform has helped us find new regulators of GLUT4 traffic, and opened up new avenues of research. We are also using the tool to initiate collborations with other groups. |
URL | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9595207/ |
Title | HeLa and Adipocyte cell lines - retention using selective hooks - GLUT4 |
Description | Cells lines expressing streptavidin-KDEL and SBP-GLUT4-mCherry so that GLUT4 traffic can be synchronised from the ER upon biotin addition. |
Type Of Material | Cell line |
Year Produced | 2022 |
Provided To Others? | No |
Impact | This is the first set of cell lines that will allow us to visualise GLUT4 traffic from the ER to its insulin sensitive compartment |
Description | Human adipocyte line |
Organisation | AstraZeneca |
Country | United Kingdom |
Sector | Private |
PI Contribution | Working with human adipocyte cell line in new RUSH assays. |
Collaborator Contribution | Provided cell line, and expertise for culturing. |
Impact | N/A |
Start Year | 2022 |
Description | Human adipocyte line - Dominique LANGIN |
Organisation | University of Toulouse |
Country | France |
Sector | Academic/University |
PI Contribution | Studying Hmad cells to maximise their funtionality in culture |
Collaborator Contribution | Provided cells |
Impact | Data added to accepted manuscript. Manuscript not yet online |
Start Year | 2023 |
Description | IPSC-cardiomyocytes - Andreia Bernardo |
Organisation | Francis Crick Institute |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Assesssment of insulin action and glucose metabolsim in IPSC-cardiomyocytes. |
Collaborator Contribution | Provision of optimised IPSC cariomyocytes. |
Impact | Subject of postodoctoral fellowshop application. |
Start Year | 2022 |
Description | Insulin resistance and GSK3 - David James |
Organisation | University of Sydney |
Department | School of Molecular Bioscience |
Country | Australia |
Sector | Academic/University |
PI Contribution | Follow up work on the role of GSK3 in adipcyte insulin resistance (cell lines). |
Collaborator Contribution | Phoshoproteomic analysis, in vivo work using Gsk3 inhbitors. |
Impact | Talks, poster presentations, publication (Nature Communications) |
Start Year | 2020 |
Description | Natalie Krahmer - Subcell proteomics |
Organisation | Helmholtz Association of German Research Centres |
Department | Helmholtz Institute for Diabetes and obesity, Munich |
Country | Germany |
Sector | Academic/University |
PI Contribution | Data sharing for adipocyte subcell proteomics |
Collaborator Contribution | Data sharing for adipocyte subcell proteomics |
Impact | None yet |
Start Year | 2024 |
Description | Plasma membrane proteomics - Mike Weekes |
Organisation | University of Cambridge |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Generation of cell models to study adipocyte insulin responses. |
Collaborator Contribution | Mass spectrometry-analysis if the plasma membrane proteome using a cell surface biotinylation assay |
Impact | Post-doctoral fellowshop application |
Start Year | 2021 |
Description | Programming cultured adipocyte metabolism - Christian Frezza |
Organisation | University of Cologne |
Country | Germany |
Sector | Academic/University |
PI Contribution | Development of new cell culture conditions to make adipocyte cell models more representive of adipose tissue. |
Collaborator Contribution | Metabolomics analysis of adipocyte metabolism (13C-Glc) under different culture conditions (higher and lower o2 tension). |
Impact | MRC underspend grant award. Talks. Manuscript in preparation. Preprint posted. |
Start Year | 2021 |
Description | Programming cultured adipocyte metabolism - Toni Vidal Puig |
Organisation | University of Cambridge |
Department | Institute of Metabolic Science (IMS) |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Cell culture expertise, adipocyte cell culture and phenotype analysis |
Collaborator Contribution | Mass spec assays for lipids, gene expression analysis, RNA-seq analysis. |
Impact | UKRI MRC underspend grant award, preprint manuscript posted |
Start Year | 2020 |
Description | RUSH GLUT4 - David Gershlick |
Organisation | University of Cambridge |
Department | Cambridge Institute for Medical Research (CIMR) |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Adipocyte cell lines, generation of all HeLa and adipocyte cell lines, imaging of cells and analysis |
Collaborator Contribution | Access to RUSH constructs, cloning guidance, imaging expertise |
Impact | Grant application - BBSRC, talks |
Start Year | 2020 |
Description | RUSH Leptin - David Gershlick and Sadaf Farooqi |
Organisation | University of Cambridge |
Department | Cambridge Institute for Medical Research (CIMR) |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Generate leptin-RUSH constricts, stble cell lines expressing these constructs and set up assays for leptin secretion, data analysis |
Collaborator Contribution | Providing human leptin mutations of interest from clinical data, secretion assay optimisation |
Impact | Internal grant application, preprint posted |
Start Year | 2021 |
Description | RUSH Leptin - David Gershlick and Sadaf Farooqi |
Organisation | University of Cambridge |
Department | Institute of Metabolic Science (IMS) |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Generate leptin-RUSH constricts, stble cell lines expressing these constructs and set up assays for leptin secretion, data analysis |
Collaborator Contribution | Providing human leptin mutations of interest from clinical data, secretion assay optimisation |
Impact | Internal grant application, preprint posted |
Start Year | 2021 |
Description | Screening genes found in genetic stuides for a role in GLUT4 traffic - Heike Vogel |
Organisation | German Institute for Nutrition Research Potsdam Rehbrücke |
Country | Germany |
Sector | Public |
PI Contribution | Screening genes found in genetic stuides for a role in GLUT4 traffic |
Collaborator Contribution | Providing genes-of-interest |
Impact | None yet |
Start Year | 2023 |
Description | Skeletal muscle IPSC - Ivo Leiberam |
Organisation | King's College London |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Assessment of insulin responses and glucose metabolism in IPSC-skeletal muscle cells. |
Collaborator Contribution | Providing IPSC-derived skeletal muscle cells for GLUT4 and metabiolic analysis. |
Impact | Submitted Cross Council research proposal |
Start Year | 2022 |
Description | Subcellular proteomics - Kathryn Lilley |
Organisation | University of Cambridge |
Department | Department of Biochemistry |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | All experimental work, expertise in adipocyte culture, optimisation of subcellular fractionation methods in adipocytes, optimisation of a lipid droplet isolation protocol. |
Collaborator Contribution | Expertise in proteomics workflows and data analysis. Access to mass spectrometers |
Impact | student poster presentations |
Start Year | 2020 |
Description | TRARG1 collaboration with Frances Brodsky |
Organisation | University College London |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Tools and cell biology expertise to study TRARG1 and its role in insulin action in adipocytes. |
Collaborator Contribution | Expertise for stuyding GLUT4 tarfficing in cultured muscle cells. Bioinformatics expertise . |
Impact | BioRxiv preprint. BBSRC grant submitted (responsive mode) |
Start Year | 2020 |
Description | Widening participation - lab work experience |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Schools |
Results and Impact | hpsted 15 a-level studetns for a week to give expereince of medical research |
Year(s) Of Engagement Activity | 2023 |