Publications by authors named "Alison Heather"

Objective: Androgen insensitivity syndrome (AIS) due to androgen receptor (AR) mutations creates a spectrum of clinical presentations based on residual AR function with the mildest impairment creating mild AIS (MAIS) whose undefined molecular mechanism and subtle clinical features leave it less understood and underdiagnosed.

Design: In silico modeling and in vitro androgen bioassay of the mutated AR are used to identify its structural and physiological mechanism. Clinical features and responses to high-dose testosterone treatment of three cases of MAIS across a six-generation family pedigree are described.

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  • - Evidence indicates that GABA neurons in the preoptic area, which sense estradiol, play a crucial role in triggering the preovulatory surge for ovulation in female mice.
  • - Researchers used CRISPR-Cas9 to reduce estrogen receptor alpha (ESR1) in GABA neurons, discovering that deletion in these neurons led to decreased activity in gonadotropin-releasing hormone (GnRH) neurons during the surge.
  • - Analysis revealed that GABA neurons expressing kisspeptin are vital for the LH surge, as mice lacking kisspeptin activity showed continuous estrus and no surge activation, though they maintained pulsatile LH release.
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  • Researchers investigated how estrogen affects the GnRH pulse generator in mice, revealing significant changes in pulse generator activity influenced by estradiol.
  • Mice lacking the ESR1 receptor specifically in kisspeptin neurons exhibited altered GnRH activity resembling that of ovariectomized mice, suggesting the importance of ESR1 in this feedback mechanism.
  • Using CRISPR-Cas9, the team showed that reduced ESR1 expression in arcuate nucleus kisspeptin neurons led to altered GnRH pulse patterns, highlighting estrogen's role in regulating fertility through these neurons.
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There is increasing debate as to whether transwoman athletes should be included in the elite female competition. Most elite sports are divided into male and female divisions because of the greater athletic performance displayed by males. Without the sex division, females would have little chance of winning because males are faster, stronger, and have greater endurance capacity.

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  • * Ca/calmodulin-dependent kinase II (CaMKII) plays various roles in VSMCs, with multiple isoforms and splice variants but their specific functions in blood vessels are still not fully understood.
  • * The review highlights the importance of studying different CaMKII splice variants to better understand their effects on vascular health, emphasizing the need for further research on their potential harmful and protective roles.
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Recent studies have highlighted the potential role of 11oxygenated (keto or hydroxy) androgens in human reproductive function with 11keto androgens circulating at concentrations comparable with testosterone in women and children. However, the intrinsic androgenic bioactivities of 11 keto and hydroxy androgens are not fully characterized. We therefore investigated the full androgen dose-response curves using complementary in vitro yeast and mammalian (HEK293) host cell bioassays of 11 keto and hydroxy derivatives of the potent androgens, testosterone (T) and dihydrotestosterone (DHT), compared with their parent non-11 oxygenated steroids together with the pro-androgen precursor (androstenedione (A)) and metabolites (androstanedione, androsterone).

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Androgens, both steroidal and nonsteroidal in nature, are among the most commonly misused substances in competitive sports. Their recognized anabolic and performance enhancing effects through short- and long-term physiological adaptations make them popular. Androgens exist as natural steroids, or are chemically synthesized as anabolic androgenic steroids (AAS) or selective androgen receptor modulators (SARMs).

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  • - Androgens are commonly abused as performance-enhancing drugs in sports, with existing detection methods struggling to identify novel structures, leading to the need for new screening techniques.
  • - A new cell-free bioassay was developed to detect androgens functionally, starting with an in vitro method that produces a reporter protein in response to testosterone.
  • - The final version of this bioassay, leveraging RNA technology, showed improved sensitivity for testosterone detection and the potential for identifying other androgenic compounds, making it more accessible and suitable for high-throughput testing.
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Health is a pre-requisite for optimal performance yet the parameters which govern health and performance of elite female athletes are little understood. The aim of this study was to quantify the health status of elite female athletes, and understand sociocultural factors influencing that status. The survey addressed demographic, health and athletic performance history, training load, contraceptive use, sport-specific appearance and performance pressures, and communication barriers.

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  • - Altrenogest is a progestogen used in female racehorses to suppress oestrus and minimize behavior distractions during training and competition.
  • - A study tested the androgen potency of altrenogest using a kidney cell bioassay, finding that it has high potency compared to testosterone, but is weaker than β-trenbolone.
  • - The research confirms that altrenogest activates the androgen receptor effectively at doses used in racing and maintains this activity outside of the body, indicating its significant androgenic effects in horses.
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We support gender equality and freedoms in cases in which 'like equals like'. Such inclusion is central to a progressive society. However, inclusion could potentially conflict with fairness in cases concerning transgendered athletes in elite sport.

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Differences in size or composition of existing plaques at the initiation of estrogen (E2) therapy may underpin evidence of increased risk of atherosclerosis-associated clinical sequelae. We investigated whether E2 had divergent effects on actively-growing versus established-advanced atherosclerotic lesions. Eight weeks of subcutaneous bi-weekly injections of 3 µg/g 17β-estradiol ( = 18) or vehicle control ( = 22) were administered to female Apolipoprotein null-mice aged 25- or 45 weeks old.

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Hemapolin (2α,3α-epithio-17α-methyl-5α-androstan-17β-ol) is a designer steroid that is an ingredient in several "dietary" and "nutritional" supplements available online. As an unusual chemical modification to the steroid A-ring could allow this compound to pass through antidoping screens undetected, the metabolism of hemapolin was investigated by an in vivo equine drug administration study coupled with GC-MS analysis. Following administration of synthetically prepared hemapolin to a thoroughbred horse, madol (17α-methyl-5α-androst-2-en-17β-ol), reduced and dihydroxylated madol (17α-methyl-5α-androstane-2β,3α,17β-triol), and the isomeric enone metabolites 17β-hydroxy-17α-methyl-5α-androst-3-en-2-one and 17β-hydroxy-17α-methyl-5α-androst-2-en-4-one, were detected and confirmed in equine urine extracts by comparison with a library of synthetically derived reference materials.

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Background: Apolipoprotein-AI (apo-AI) is the major apolipoprotein found in high density lipoprotein particles (HDLs). We previously demonstrated that apo-AI injected directly into high-fat diet fed mice improved insulin sensitivity associated with decreased hepatic inflammation. While our data provides compelling proof of concept, apoA-I mimetic peptides are more clinically feasible.

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The inclusion of elite transwomen athletes in sport is controversial. The recent International Olympic Committee (IOC) (2015) guidelines allow transwomen to compete in the women's division if (amongst other things) their testosterone is held below 10 nmol/L. This is significantly higher than that of cis-women.

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New Findings: What is the topic of this review? We review methodological considerations for the inclusion of women in sex and menstrual cycle phase comparison studies. What advances does it highlight? Improving the methodological design for studies exploring sex differences, menstrual cycle phase differences and/or endogenous versus exogenous female sex hormones will help to close the gap in our understanding of the effects of endogenous and exogenous hormones on exercise science and sports medicine outcomes.

Abstract: In recent years, the increase in scientific literature exploring sex differences has been beneficial to both clinicians and allied health science professionals, although female athletes are still significantly under-represented in sport and exercise science research.

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Signalling mechanisms within and between cells of the vasculature enable function and maintain homeostasis. However, a number of these mechanisms also contribute to the pathophysiology of vascular disease states. The multifunctional signalling molecule calcium/calmodulin-dependent kinase II (CaMKII) has been shown to have critical functional effects in many tissue types.

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Both athletes and the general population use nutritional supplements. Athletes often turn to supplements hoping that consuming the supplement will help them be more competitive and healthy, while the general population hopes to improve body image or vitality. While many supplements contain ingredients that may have useful properties, there are supplements that are contaminated with compounds that are banned for use in sport or have been deliberately adulterated to fortify a supplement with an ingredient that will produce the advertised effect.

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Facioscapulohumeral muscular dystrophy (FSHD) is an inherited myopathy affecting approximately 1 in 7500 individuals worldwide. It is a progressive disease characterised by skeletal muscle weakness and wasting. A genetic mutation on the 4q35 chromosome results in the expression of the double homeobox 4 gene (DUX4) which drives oxidative stress, inflammation, toxicity, and atrophy within the skeletal muscle.

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Objective: Vascular calcification is associated with increased risk of myocardial infarction and stroke. The objective of this work was to examine the ability of 17β-estradiol (E2) to stimulate calcification of vascular smooth muscle cells (VSMC) in vivo, using aged apolipoprotein E-null mice with advanced atherosclerotic lesions, and subsequently to explore underlying mechanisms in vitro.

Approach And Results: Silastic E2 capsules were implanted into male and female apolipoprotein E-null mice aged 34 weeks.

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In 2012, seized capsules containing white powder were analyzed to show the presence of unknown steroid-related compounds. Subsequent gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) investigations identified a mixture of 3α- and 3β- isomers of the novel compound; 3-chloro-17α-methyl-5α-androstan-17β-ol. Synthesis of authentic reference materials followed by comparison of NMR, GC-MS and gas chromatography-tandem mass spectrometry (GC-MS/MS) data confirmed the finding of a new 'designer' steroid.

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Sport supplements containing steroids never approved for therapeutic use have the potential for abuse by athletes. Most are marketed online and may contain undisclosed steroids yet are readily available despite lacking toxicological or pharmacological evaluation. In this study, 18 supplements purchased online underwent organic solvent extraction to isolate any steroids they contained.

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Oxidative stress and inflammation, leading to endothelial dysfunction, contribute to the pathogenesis of atherosclerosis. The popularity of natural product supplements has increased in recent years, especially those with purported anti-inflammatory and/or antioxidant effects. The efficacy and mechanism of many of these products are not yet well understood.

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