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Relationship: 2626

Title

A descriptive phrase which clearly defines the two KEs being considered and the sequential relationship between them (i.e., which is upstream, and which is downstream). More help

Agonism, Estrogen Receptor alpha leads to Increased, Kisspeptin signalling

Upstream event

The causing Key Event (KE) in a Key Event Relationship (KER). More help

Agonism, Estrogen Receptor alpha

Downstream event

The responding Key Event (KE) in a Key Event Relationship (KER). More help

Increased, Kisspeptin signalling

Key Event Relationship Overview

The utility of AOPs for regulatory application is defined, to a large extent, by the confidence and precision with which they facilitate extrapolation of data measured at low levels of biological organisation to predicted outcomes at higher levels of organisation and the extent to which they can link biological effect measurements to their specific causes.Within the AOP framework, the predictive relationships that facilitate extrapolation are represented by the KERs. Consequently, the overall WoE for an AOP is a reflection in part, of the level of confidence in the underlying series of KERs it encompasses. Therefore, describing the KERs in an AOP involves assembling and organising the types of information and evidence that defines the scientific basis for inferring the probable change in, or state of, a downstream KE from the known or measured state of an upstream KE. More help

AOPs Referencing Relationship

Taxonomic Applicability

Latin or common names of a species or broader taxonomic grouping (e.g., class, order, family) that help to define the biological applicability domain of the KER.In general, this will be dictated by the more restrictive of the two KEs being linked together by the KER. More help

Term	Scientific Term	Evidence	Link
rodents	rodents	High	NCBI
mammals	mammals	High	NCBI
fish	fish	Low	NCBI

Sex Applicability

An indication of the the relevant sex for this KER. More help

Sex	Evidence
Male	High
Female	High

Life Stage Applicability

An indication of the the relevant life stage(s) for this KER. More help

Term	Evidence
Adult, reproductively mature	High

Key Event Relationship Description

Provides a concise overview of the information given below as well as addressing details that aren’t inherent in the description of the KEs themselves. More help

Estrogen receptor alpha (ERα) is a nuclear receptor that can be activated by estrogens, a group of hormones involved in reproductive development. Activation of ERα promotes the transcription and regulation of physiological processes involved with the endocrine system(Christian and Moenter, 2007). Kisspeptins are a family of peptide hormones with varying amino acid lengths derived from the KISS1 gene & neurons (Nejad et al., 2017). Breakthrough research in the 2000s has shown that kisspeptins play a large role in the hypothalamic-pituitary-gonadal axis with gonadotropin circulation(Alcin et al., 2013). In particular, more recent research has shown kisspeptin neurons contain large populations of estrogen receptors, particularly ERα.

Evidence Collection Strategy

Include a description of the approach for identification and assembly of the evidence base for the KER. For evidence identification, include, for example, a description of the sources and dates of information consulted including expert knowledge, databases searched and associated search terms/strings. Include also a description of study screening criteria and methodology, study quality assessment considerations, the data extraction strategy and links to any repositories/databases of relevant references.Tabular summaries and links to relevant supporting documentation are encouraged, wherever possible. More help

Evidence Map 2.0

ID	Experimental Design	Species	Upstream Observation	Downstream Observation	Citation (first author, year)	Notes

Evidence Map

Addresses the scientific evidence supporting KERs in an AOP setting the stage for overall assessment of the AOP. More help

Title	First Author	Biological Plausibility	Dose Concordance	Temporal Concordance	Incidence Concordance

Biological Plausibility

Dose Concordance Evidence

Temporal Concordance Evidence

Incidence Concordance Evidence

Uncertainties and Inconsistencies

Addresses inconsistencies or uncertainties in the relationship including the identification of experimental details that may explain apparent deviations from the expected patterns of concordance. More help

When young female rhesus macaques were exposed to estradiol and ovariectomized, there was not a significant change in Kiss-1 expression (Eghlidi et al., 2010).

Known modulating factors

This table captures specific information on the MF, its properties, how it affects the KER and respective references.1.) What is the modulating factor? Name the factor for which solid evidence exists that it influences this KER. Examples: age, sex, genotype, diet 2.) Details of this modulating factor. Specify which features of this MF are relevant for this KER. Examples: a specific age range or a specific biological age (defined by...); a specific gene mutation or variant, a specific nutrient (deficit or surplus); a sex-specific homone; a certain threshold value (e.g. serum levels of a chemical above...) 3.) Description of how this modulating factor affects this KER. Describe the provable modification of the KER (also quantitatively, if known). Examples: increase or decrease of the magnitude of effect (by a factor of...); change of the time-course of the effect (onset delay by...); alteration of the probability of the effect; increase or decrease of the sensitivity of the downstream effect (by a factor of...) 4.) Provision of supporting scientific evidence for an effect of this MF on this KER. Give a list of references. More help

Modulating factors haven’t been evaluated yet.

Quantitative Understanding of the Linkage

Captures information that helps to define how much change in the upstream KE, and/or for how long, is needed to elicit a detectable and defined change in the downstream KE. More help

Quantitative understanding is shown below.

Response-response Relationship

Provides sources of data that define the response-response relationships between the KEs. More help

Dose concordance evidence above demonstrates a response-response relationship where lower doses of estradiol don’t elicit changes in kisspeptin levels.

Time-scale

Information regarding the approximate time-scale of the changes in KEdownstream relative to changes in KEupstream (i.e., do effects on KEdownstream lag those on KEupstream by seconds, minutes, hours, or days?). More help

5 hours after an estrogen exposure, there is evidence of a change in kisspeptin expression (Adachi et al., 2007).

Known Feedforward/Feedback loops influencing this KER

Define whether there are known positive or negative feedback mechanisms involved and what is understood about their time-course and homeostatic limits. More help

ERα and kisspeptins are involved with gonadotropin circulation within the body. It is well known that gonadotropins have both a negative and positive feedback loop depending on the circumstances. In females under proper reproductive conditions, estrogen induces positive feedback for ovulation. Under all other circumstances in females and males, estrogen induces negative feedback action to regulate levels of gonadotropins.

Domain of Applicability

A free-text section of the KER description that the developers can use to explain their rationale for the taxonomic, life stage, or sex applicability structured terms. More help

Taxonomic Applicability:
- The understanding of kisspeptins on the hypothalamus-gonadotropin- pituitary axis comes largely from rodent and mammal studies. However, there have been more studies recently in other species such as fish to determine if applicability is present which it has shown.
Sex Applicability:
- Estrogen is present in both males and females. There is sexual dimorphism in the expression of kisspeptin neurons within the hypothalamus due to the positive feedback actions present in females particularly with reproduction. .
Life Stage Applicability:
- Kisspeptin plays a role in gonadotropin circulation. As a result of gonadotropins’ role in reproduction, the applicability can be directed towards reproductively mature organisms and developing organisms.