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AOP: 497

Title

A descriptive phrase which references both the Molecular Initiating Event and Adverse Outcome.It should take the form “MIE leading to AO”. For example, “Aromatase inhibition leading to reproductive dysfunction” where Aromatase inhibition is the MIE and reproductive dysfunction the AO. In cases where the MIE is unknown or undefined, the earliest known KE in the chain (i.e., furthest upstream) should be used in lieu of the MIE and it should be made clear that the stated event is a KE and not the MIE.  More help

ERa inactivation alters mitochondrial functions and insulin signalling in skeletal muscle and leads to insulin resistance and metabolic syndrome

Short name
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ERa inactivation leads to insulin resistance in skeletal muscle and metabolic syndrome
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Handbook Version v2.6

Graphical Representation

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Click to download graphical representation template Explore AOP in a Third Party Tool

Authors

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Min Ji Kim

Jean-Pascal De Bandt

Antoine Girardon

Etienne Blanc

Xavier Coumoul

Karine Audouze

Point of Contact

The user responsible for managing the AOP entry in the AOP-KB and controlling write access to the page by defining the contributors as described in the next section.   More help
Min Ji Kim   (email point of contact)

Contributors

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  • Min Ji Kim
  • Jean-Pascal de Bandt
  • Etienne Blanc
  • Xavier COUMOUL
  • Karine Audouze

Coaches

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OECD Information Table

Provides users with information concerning how actively the AOP page is being developed and whether it is part of the OECD Workplan and has been reviewed and/or endorsed. OECD Project: Assigned upon acceptance onto OECD workplan. This project ID is managed and updated (if needed) by the OECD. OECD Status: For AOPs included on the OECD workplan, ‘OECD status’ tracks the level of review/endorsement of the AOP . This designation is managed and updated by the OECD. Journal-format Article: The OECD is developing co-operation with Scientific Journals for the review and publication of AOPs, via the signature of a Memorandum of Understanding. When the scientific review of an AOP is conducted by these Journals, the journal review panel will review the content of the Wiki. In addition, the Journal may ask the AOP authors to develop a separate manuscript (i.e. Journal Format Article) using a format determined by the Journal for Journal publication. In that case, the journal review panel will be required to review both the Wiki content and the Journal Format Article. The Journal will publish the AOP reviewed through the Journal Format Article. OECD iLibrary published version: OECD iLibrary is the online library of the OECD. The version of the AOP that is published there has been endorsed by the OECD. The purpose of publication on iLibrary is to provide a stable version over time, i.e. the version which has been reviewed and revised based on the outcome of the review. AOPs are viewed as living documents and may continue to evolve on the AOP-Wiki after their OECD endorsement and publication.   More help
OECD Project # OECD Status Reviewer's Reports Journal-format Article OECD iLibrary Published Version
This AOP was last modified on July 04, 2024 12:38

Revision dates for related pages

Page Revision Date/Time
Estrogen receptor alpha inactivation April 10, 2023 13:29
Decreased, Mitochondrial fatty acid beta-oxidation September 16, 2017 10:14
Increased, Reactive oxygen species April 10, 2024 17:33
Impaired insulin signaling May 25, 2023 09:46
Metabolic syndrome May 25, 2023 09:51
Mitochondrial dysfunction April 17, 2024 08:26
Insulin resistance, increased May 26, 2023 06:34
Oxidative Stress November 15, 2024 10:33
ERa inactivation leads to Decreased, Mitochondrial fatty acid beta-oxidation May 25, 2023 10:01
ERa inactivation leads to Increased, Reactive oxygen species May 25, 2023 10:03
Decreased, Mitochondrial fatty acid beta-oxidation leads to Mitochondrial dysfunction March 13, 2024 17:25
Increased, Reactive oxygen species leads to Oxidative Stress August 02, 2024 15:40
Mitochondrial dysfunction leads to Impaired insulin signaling March 13, 2024 17:26
Oxidative Stress leads to Impaired insulin signaling July 04, 2024 12:29
Impaired insulin signaling leads to Insulin resistance, increased April 09, 2024 16:51
Insulin resistance, increased leads to Metabolic syndrome April 09, 2024 16:51
Oxidative Stress leads to Mitochondrial dysfunction May 31, 2024 17:58

Abstract

A concise and informative summation of the AOP under development that can stand-alone from the AOP page. The aim is to capture the highlights of the AOP and its potential scientific and regulatory relevance. More help

Estrogens are not only important in the development and functions of the reproductive system, but also play a role in metabolic functions and insulin sensitivity. Thus, before menopause,  women display higher insulin sensitivity and lower propensity to develop metabolic dysfunction-related diseases such as insulin resistance, type 2 diabetes, cancers and cardiovascular diseases than men but, after menopause, incidence of these diseases is similar in both sex [1]. In parallel, hormone replacement therapy has positive effects on insulin resistance [2]. Similarly, men with a mutation in the aromatase gene, who don’t have circulating estrogen, develop insulin resistance that can be reversed by estrogen therapy [3].

Skeletal muscle is known to play a central role in the development of insulin resistance (IR). Due to the important mass of skeletal muscle (30 to 40% of total body mass), any defect in glucose entry into the muscle cells, caused by muscle IR, significantly affects whole body glucose disposition. Subsequently, IR in skeletal muscle favors hyperglycemia and increase the risk of type 2 diabetes [4]. The importance of estrogens and their effects mediated through ERa in insulin resistance was suggested by whole body ERa knock-out (KO) and muscle-specific ERa KO mice that are obese and insulin resistant [5,6]. A negative association between muscle ERa expression and fat mass or insulinemia is observed in women and in genetically obese mice emphasizing the importance of muscle ERa signaling in insulin sensitivity [6]. Thus, the alterations resulting from reduced muscle ERa activity is important to consider to better understand mechanisms leading to muscle insulin resistance.

Decreased mitochondrial oxidative capacity, increased production of reactive oxygen species and impaired insulin signaling should be considered as they are known to be key features of insulin-resistant muscle [7] and are also present in ERa KO mice [5,6].

Thus, the AOP that we propose here links the inactivation of ERa in skeletal muscle to one of the hallmarks of the metabolic syndrome that is insulin resistance taking account the following events “decreased mitochondrial fatty acid oxidation”, “increased reactive oxygen species”, “mitochondrial dysfunction”, “increased oxidative stress” and “impaired insulin signaling”.

AOP Development Strategy

Context

Used to provide background information for AOP reviewers and users that is considered helpful in understanding the biology underlying the AOP and the motivation for its development.The background should NOT provide an overview of the AOP, its KEs or KERs, which are captured in more detail below. More help

Strategy

Provides a description of the approaches to the identification, screening and quality assessment of the data relevant to identification of the key events and key event relationships included in the AOP or AOP network.This information is important as a basis to support the objective/envisaged application of the AOP by the regulatory community and to facilitate the reuse of its components.  Suggested content includes a rationale for and description of the scope and focus of the data search and identification strategy/ies including the nature of preliminary scoping and/or expert input, the overall literature screening strategy and more focused literature surveys to identify additional information (including e.g., key search terms, databases and time period searched, any tools used). More help

Summary of the AOP

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Events:

Molecular Initiating Events (MIE)
An MIE is a specialised KE that represents the beginning (point of interaction between a prototypical stressor and the biological system) of an AOP. More help
Key Events (KE)
A measurable event within a specific biological level of organisation. More help
Adverse Outcomes (AO)
An AO is a specialized KE that represents the end (an adverse outcome of regulatory significance) of an AOP. More help
Type Event ID Title Short name
MIE 2126 Estrogen receptor alpha inactivation ERa inactivation
KE 179 Decreased, Mitochondrial fatty acid beta-oxidation Decreased, Mitochondrial fatty acid beta-oxidation
KE 1115 Increased, Reactive oxygen species Increased, Reactive oxygen species
KE 177 Mitochondrial dysfunction Mitochondrial dysfunction
KE 1392 Oxidative Stress Oxidative Stress
KE 2144 Impaired insulin signaling Impaired insulin signaling
AO 2119 Insulin resistance, increased Insulin resistance, increased
AO 2145 Metabolic syndrome Metabolic syndrome

Relationships Between Two Key Events (Including MIEs and AOs)

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Title Adjacency Evidence Quantitative Understanding
ERa inactivation leads to Decreased, Mitochondrial fatty acid beta-oxidation adjacent High
ERa inactivation leads to Increased, Reactive oxygen species adjacent High
Decreased, Mitochondrial fatty acid beta-oxidation leads to Mitochondrial dysfunction adjacent High
Increased, Reactive oxygen species leads to Oxidative Stress adjacent High
Mitochondrial dysfunction leads to Impaired insulin signaling adjacent Moderate
Oxidative Stress leads to Impaired insulin signaling adjacent High
Impaired insulin signaling leads to Insulin resistance, increased adjacent High
Insulin resistance, increased leads to Metabolic syndrome adjacent High
Oxidative Stress leads to Mitochondrial dysfunction adjacent High

Network View

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Prototypical Stressors

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Life Stage Applicability

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Taxonomic Applicability

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Sex Applicability

The sex for which the AOP is known to be applicable. More help

Overall Assessment of the AOP

Addressess the relevant biological domain of applicability (i.e., in terms of taxa, sex, life stage, etc.) and Weight of Evidence (WoE) for the overall AOP as a basis to consider appropriate regulatory application (e.g., priority setting, testing strategies or risk assessment). More help

Domain of Applicability

Addressess the relevant biological domain(s) of applicability in terms of sex, life-stage, taxa, and other aspects of biological context. More help

Essentiality of the Key Events

The essentiality of KEs can only be assessed relative to the impact of manipulation of a given KE (e.g., experimentally blocking or exacerbating the event) on the downstream sequence of KEs defined for the AOP. Consequently, evidence supporting essentiality is assembled on the AOP page, rather than on the independent KE pages that are meant to stand-alone as modular units without reference to other KEs in the sequence. The nature of experimental evidence that is relevant to assessing essentiality relates to the impact on downstream KEs and the AO if upstream KEs are prevented or modified. This includes: Direct evidence: directly measured experimental support that blocking or preventing a KE prevents or impacts downstream KEs in the pathway in the expected fashion. Indirect evidence: evidence that modulation or attenuation in the magnitude of impact on a specific KE (increased effect or decreased effect) is associated with corresponding changes (increases or decreases) in the magnitude or frequency of one or more downstream KEs. More help

Evidence Assessment

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Known Modulating Factors

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Modulating Factor (MF) Influence or Outcome KER(s) involved
     

Quantitative Understanding

Optional field to provide quantitative weight of evidence descriptors.  More help

Considerations for Potential Applications of the AOP (optional)

Addressess potential applications of an AOP to support regulatory decision-making.This may include, for example, possible utility for test guideline development or refinement, development of integrated testing and assessment approaches, development of (Q)SARs / or chemical profilers to facilitate the grouping of chemicals for subsequent read-across, screening level hazard assessments or even risk assessment. More help

References

List of the literature that was cited for this AOP. More help

[1]       M.C. Carr, The emergence of the metabolic syndrome with menopause, J Clin Endocrinol Metab. 88 (2003) 2404–2411. https://doi.org/10.1210/jc.2003-030242.

[2]       F. Mauvais-Jarvis, J.E. Manson, J.C. Stevenson, V.A. Fonseca, Menopausal Hormone Therapy and Type 2 Diabetes Prevention: Evidence, Mechanisms, and Clinical Implications, Endocr Rev. 38 (2017) 173–188. https://doi.org/10.1210/er.2016-1146.

[3]       V. Rochira, B. Madeo, L. Zirilli, G. Caffagni, L. Maffei, C. Carani, Oestradiol replacement treatment and glucose homeostasis in two men with congenital aromatase deficiency: evidence for a role of oestradiol and sex steroids imbalance on insulin sensitivity in men, Diabet Med. 24 (2007) 1491–1495. https://doi.org/10.1111/j.1464-5491.2007.02304.x.

[4]       R.A. DeFronzo, D. Tripathy, Skeletal muscle insulin resistance is the primary defect in type 2 diabetes, Diabetes Care. 32 Suppl 2 (2009) S157-163. https://doi.org/10.2337/dc09-S302.

[5]       V. Ribas, M.T.A. Nguyen, D.C. Henstridge, A.-K. Nguyen, S.W. Beaven, M.J. Watt, A.L. Hevener, Impaired oxidative metabolism and inflammation are associated with insulin resistance in ERalpha-deficient mice, Am J Physiol Endocrinol Metab. 298 (2010) E304-319. https://doi.org/10.1152/ajpendo.00504.2009.

[6]       V. Ribas, B.G. Drew, Z. Zhou, J. Phun, N.Y. Kalajian, T. Soleymani, P. Daraei, K. Widjaja, J. Wanagat, T.Q. de Aguiar Vallim, A.H. Fluitt, S. Bensinger, T. Le, C. Radu, J.P. Whitelegge, S.W. Beaven, P. Tontonoz, A.J. Lusis, B.W. Parks, L. Vergnes, K. Reue, H. Singh, J.C. Bopassa, L. Toro, E. Stefani, M.J. Watt, S. Schenk, T. Akerstrom, M. Kelly, B.K. Pedersen, S.C. Hewitt, K.S. Korach, A.L. Hevener, Skeletal muscle action of estrogen receptor α is critical for the maintenance of mitochondrial function and metabolic homeostasis in females, Sci Transl Med. 8 (2016) 334ra54. https://doi.org/10.1126/scitranslmed.aad3815.

[7]       S. Di Meo, S. Iossa, P. Venditti, Skeletal muscle insulin resistance: role of mitochondria and other ROS sources, J Endocrinol. 233 (2017) R15–R42. https://doi.org/10.1530/JOE-16-0598.