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1.
J Sci Med Sport ; 2024 May 31.
Article in English | MEDLINE | ID: mdl-38960811

ABSTRACT

Polycystic ovary syndrome (PCOS) is the most prevalent endocrine condition amongst females of reproductive age, leading to lifelong cardiometabolic, reproductive, psychological, and dermatologic symptoms as well as a reduced quality of life. Lifestyle interventions, which can include structured exercise programmes delivered by appropriately trained exercise professionals such as clinical exercise physiologists, are considered first-line strategies in PCOS management due to their therapeutic effects on various health outcomes and quality of life. This position statement builds on the 2023 International Evidence-based Guideline for the Assessment and Management of PCOS and describes the role of the exercise professional in the context of the multidisciplinary care team which includes physicians and allied health professionals. This position statement aims to equip exercise professionals with a broad understanding of the pathophysiology of PCOS, how it is diagnosed and managed in clinical practice, and evidence- and consensus-based recommendations for physical activity and exercise in PCOS management. In line with the physical activity recommendations for the general public, individuals with PCOS should aim to undertake between 150 to 300min of moderate-intensity or 75 to 150min of vigorous-intensity aerobic activity per week, or an equivalent combination of both spread throughout the week. Additionally, muscle-strengthening activities on two non-consecutive days per week are recommended to maintain health and prevent weight gain. For further health benefits and to achieve modest weight loss, individuals with PCOS should aim for a minimum of 250min of moderate-intensity or 150min of vigorous-intensity aerobic activity per week, or an equivalent combination of both spread throughout the week, plus muscle-strengthening activities on two non-consecutive days per week. Adolescents with PCOS should aim for a minimum of 60min moderate- to vigorous-intensity activity each day, incorporating muscle- and bone-strengthening activities three times per week. Finally, exercise professionals should consider the significant psychological burden, including weight stigma, and the high prevalence of comorbidities amongst individuals with PCOS and take appropriate measures to deliver safe and efficacious exercise interventions.

2.
Psychol Sport Exerc ; 64: 102325, 2023 01.
Article in English | MEDLINE | ID: mdl-37665810

ABSTRACT

BACKGROUND: Women with polycystic ovary syndrome (PCOS) experience general and PCOS-specific barriers that limit their engagement with exercise and contribute to high attrition from exercise programs, hindering the potential benefits of exercise to address their increased cardio-metabolic risk. A positive remembered affective response can predict future intentions and adherence to exercise prescription. OBJECTIVES: To compare the longitudinal changes in remembered affect to high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) in women with PCOS and to determine whether longitudinal changes in remembered affect are correlated with changes in fitness, body mass index, adherence and exercise enjoyment. METHODS: Physically inactive, overweight women with PCOS were randomly assigned to 12 weeks of either HIIT (n = 15) or MICT (n = 14) (3 sessions per week). Remembered affective valence (Feeling Scale) was collected after each exercise session. Cardiorespiratory fitness (VO2peak) was assessed at baseline and post-intervention. Exercise enjoyment was assessed post-intervention. RESULTS: The longitudinal changes in the remembered affect were more positive in the HIIT group compared to MICT (ß = 0.017, p = 0.047). HIIT was also considered more enjoyable than MICT (p = 0.002). Adherence was high in both groups (>90%). We found a moderate correlation with longitudinal changes between the remembered affect and change in fitness (rs = 0.398) and exercise enjoyment (rs = 0.376) using the combined group, however, these were not statistically significant (p = 0.054 and p = 0.064, respectively). CONCLUSIONS: HIIT demonstrated a more positive longitudinal remembered affective response and greater exercise enjoyment compared to MICT in overweight women with PCOS.


Subject(s)
High-Intensity Interval Training , Polycystic Ovary Syndrome , Humans , Female , Overweight/complications , Polycystic Ovary Syndrome/complications , Pleasure , Happiness
3.
J Physiol ; 601(10): 1851-1867, 2023 05.
Article in English | MEDLINE | ID: mdl-36999349

ABSTRACT

Immobilization leads to muscle wasting and insulin resistance, particularly during ageing. It has been suggested that undercarboxylated osteocalcin (ucOC) improves muscle mass and glucose metabolism. Bisphosphonates, an anti-osteoporosis treatment, might protect muscle wasting independent of ucOC. We hypothesize that the combination of ucOC and ibandronate (IBN) treatments has superior protective effects against immobilization-induced muscle wasting and insulin resistance than either treatment alone. C57BL/6J mice were hindlimb-immobilized for two weeks, with injections of vehicle, ucOC (90 ng/g daily) and/or IBN (2 µg/g weekly). Insulin/oral glucose tolerance tests (ITT/OGTT) were performed. Immediately after immobilization, muscles (extensor digitorum longus (EDL), soleus, tibialis anterior, gastrocnemius and quadriceps) were isolated and measured for muscle mass. Insulin-stimulated glucose uptake (EDL and soleus) was examined. Phosphorylation/expression of proteins in anabolic/catabolic pathways were examined in quadriceps. Primary human myotubes derived from older adult muscle biopsies were treated with ucOC and/or IBN, then signalling proteins were analysed. Combined treatment, but not individual treatments, significantly increased the muscle weight/body weight ratio in immobilized soleus (31.7%; P = 0.013) and quadriceps (20.0%; P = 0.0008) muscles, concomitant with elevated p-Akt (S473)/Akt ratio (P = 0.0047). Combined treatment also enhanced whole-body glucose tolerance (16.6%; P = 0.0011). In human myotubes, combined treatment stimulated greater activation of ERK1/2 (P = 0.0067 and 0.0072) and mTOR (P = 0.036), and led to a lesser expression of Fbx32 (P = 0.049) and MuRF1 (P = 0.048) than individual treatments. These findings suggest a potential therapeutic role for the ucOC and bisphosphonates combination in protecting against muscle wasting induced by immobilization and ageing. KEY POINTS: It has been suggested that undercarboxylated osteocalcin (ucOC) improves muscle mass and glucose metabolism. Bisphosphonates, an anti-osteoporosis treatment, might protect against muscle wasting independent of ucOC. The combination treatment of ucOC and ibandronate was shown to exert a greater therapeutic effect against immobilization-induced muscle wasting, and led to greater activation of anabolic pathway and less expression of catabolic signalling proteins in myotubes derived from older adults, compared with individual treatments. The combination treatment was found to improve whole-body glucose tolerance. Our findings suggest a potential therapeutic role for the ucOC and bisphosphonates combination in protecting against muscle wasting induced by immobilization and ageing.


Subject(s)
Insulin Resistance , Animals , Mice , Humans , Aged , Osteocalcin/metabolism , Osteocalcin/pharmacology , Ibandronic Acid/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Hindlimb Suspension , Mice, Inbred C57BL , Muscular Atrophy/drug therapy , Muscular Atrophy/etiology , Muscular Atrophy/prevention & control , Muscle, Skeletal/metabolism , Insulin/metabolism , Glucose/metabolism
4.
Sci Rep ; 13(1): 3025, 2023 02 21.
Article in English | MEDLINE | ID: mdl-36810865

ABSTRACT

Women with PCOS have substantially greater symptoms of depression and anxiety, and a lower health-related quality of life (HRQoL) compared to women without PCOS. The aim of this study was to determine if high-intensity interval training (HIIT) could provide greater improvements in mental health outcomes than standard moderate-intensity continuous training (MICT). Twenty-nine overweight women with PCOS aged 18-45 years were randomly assigned to 12 weeks of either MICT (60-75% HRpeak, N = 15) or HIIT (> 90% HRpeak, N = 14). Outcome measures included symptoms of depression, anxiety and stress (DASS-21), general HRQoL (SF-36) and PCOS specific HRQoL (PCOSQ) collected at baseline and post-intervention. Reductions in depression (Δ - 1.7, P = 0.005), anxiety (Δ - 3.4, P < 0.001) and stress (Δ - 2.4, P = 0.003) scores were observed in the HIIT group, while MICT only resulted in a reduction in stress scores (Δ - 2.9, P = 0.001). Reductions in anxiety scores were significantly higher in the HIIT group compared to the MICT group (ß = - 2.24, P = 0.020). Both HIIT and MICT significantly improved multiple domain scores from the SF-36 and PCOSQ. This study highlights the potential of HIIT for improving mental health and HRQoL in overweight women with PCOS. HIIT may be a viable strategy to reduce symptoms of depression and anxiety in women with PCOS, however, large-scale studies are required to confirm these findings.Trial registration number: ACTRN12615000242527.


Subject(s)
High-Intensity Interval Training , Polycystic Ovary Syndrome , Humans , Female , Quality of Life , Overweight , Mental Health , High-Intensity Interval Training/methods
5.
J Endocrinol ; 255(1): R1-R26, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35980384

ABSTRACT

Polycystic ovary syndrome (PCOS) is a common endocrine condition characterised by a range of reproductive, endocrine, metabolic and psychological abnormalities. Reports estimate that around 10% of women of reproductive age are affected by PCOS, representing a significant prevalence worldwide, which poses a high economic health burden. As the origin of PCOS remains largely unknown, there is neither a cure nor mechanism-based treatments leaving patient management suboptimal and focused solely on symptomatic treatment. However, if the underlying mechanisms underpinning the development of PCOS were uncovered then this would pave the way for the development of new interventions for PCOS. Recently, there have been significant advances in our understanding of the underlying pathways likely involved in PCOS pathogenesis. Key insights include the potential involvement of androgens, insulin, anti-Müllerian hormone and transforming growth factor beta in the development of PCOS. This review will summarise the significant scientific discoveries on these factors that have enhanced our knowledge of the mechanisms involved in the development of PCOS and discuss the impact these insights may have in shaping the future development of effective strategies for women with PCOS.


Subject(s)
Insulin Resistance , Polycystic Ovary Syndrome , Androgens/metabolism , Anti-Mullerian Hormone/metabolism , Female , Humans , Insulin , Polycystic Ovary Syndrome/metabolism
6.
J Physiol ; 600(14): 3313-3330, 2022 07.
Article in English | MEDLINE | ID: mdl-35760527

ABSTRACT

Polycystic ovary syndrome (PCOS) is characterised by a hormonal imbalance affecting the reproductive and metabolic health of reproductive-aged women. Exercise is recommended as a first-line therapy for women with PCOS to improve their overall health; however, women with PCOS are resistant to the metabolic benefits of exercise training. Here, we aimed to gain insight into the mechanisms responsible for such resistance to exercise in PCOS. We employed an in vitro approach with electrical pulse stimulation (EPS) of cultured skeletal muscle cells to explore whether myotubes from women with PCOS have an altered gene expression signature in response to contraction. Following EPS, 4719 genes were differentially expressed (false discovery rate <0.05) in myotubes from women with PCOS compared to 173 in healthy women. Both groups included genes involved in skeletal muscle contraction. We also determined the effect of two transforming growth factor ß (TGFß) ligands that are elevated in plasma of women with PCOS, TGFß1 and anti-Müllerian hormone (AMH), alone and on the EPS-induced response. While AMH (30 ng/ml) had no effect, TGFß1 (5 ng/ml) induced the expression of extracellular matrix genes and impaired the exercise-like transcriptional signature in myotubes from women with and without PCOS in response to EPS by interfering with key processes related to muscle contraction, calcium transport and actin filament. Our findings suggest that while the fundamental gene expression responses of skeletal muscle to contraction is intact in PCOS, circulating factors like TGFß1 may be responsible for the impaired adaptation to exercise in women with PCOS. KEY POINTS: Gene expression responses to in vitro contraction (electrical pulse stimulation, EPS) are altered in myotubes from women with polycystic ovary syndrome (PCOS) compared to healthy controls, with an increased expression of genes related to pro-inflammatory pathways. Transforming growth factor ß1 (TGFß1) upregulates genes related to extracellular matrix remodelling and reduces the expression of contractile genes in myotubes, regardless of the donor's health status. TGFß1 alters the gene expression response to EPS, providing a possible mechanism for the impaired exercise adaptations in women with PCOS.


Subject(s)
Polycystic Ovary Syndrome , Adult , Anti-Mullerian Hormone/genetics , Anti-Mullerian Hormone/metabolism , Female , Humans , Muscle Fibers, Skeletal/metabolism , Polycystic Ovary Syndrome/genetics , Polycystic Ovary Syndrome/metabolism , Transcriptome , Transforming Growth Factor beta1/metabolism
7.
Hum Reprod ; 37(5): 1018-1029, 2022 05 03.
Article in English | MEDLINE | ID: mdl-35325125

ABSTRACT

STUDY QUESTION: Does 12 weeks of high-intensity interval training (HIIT) result in greater improvements in cardio-metabolic and reproductive outcomes compared to standard moderate-intensity continuous training (MICT) in women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: HIIT offers greater improvements in aerobic capacity, insulin sensitivity and menstrual cyclicity, and larger reductions in hyperandrogenism compared to MICT. WHAT IS KNOWN ALREADY: Exercise training is recognized to improve clinical outcomes in women with PCOS, but little is known about whether HIIT results in greater health outcomes compared to standard MICT. STUDY DESIGN, SIZE, DURATION: This was a two-armed randomized clinical trial enrolling a total of 29 overweight women with PCOS between May 2016 and November 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with PCOS aged 18-45 years were randomly assigned to 12 weeks of either MICT (60-75% peak heart rate, N = 14) or HIIT (>90% peak heart rate, N = 15), each completed three times per week. The primary clinical outcomes were aerobic capacity (VO2peak) and insulin sensitivity (euglycaemic-hyperinsulinaemic clamp). Secondary outcomes included hormonal profiles, menstrual cyclicity and body composition. MAIN RESULTS AND THE ROLE OF CHANCE: Both HIIT and MICT improved VO2peak (HIIT; Δ 5.8 ± 2.6 ml/kg/min, P < 0.001 and MICT; Δ 3.2 ± 2 ml/kg/min, P < 0.001), however, the HIIT group had a greater improvement in aerobic capacity compared to MICT (ß = 2.73 ml/kg/min, P = 0.015). HIIT increased the insulin sensitivity index compared to baseline (Δ 2.3 ± 4.4 AU, P = 0.007) and MICT (ß = 0.36 AU, P = 0.030), and caused higher increases in sex hormone-binding globulin compared to MICT (ß = 0.25 nmol/l, P = 0.002). HIIT participants were 7.8 times more likely to report improved menstrual cyclicity than those in the MICT group (odds ratio 7.8, P = 0.04). LIMITATIONS, REASONS FOR CAUTION: This study has a small sample size and the findings of the effect of the exercise interventions are limited to overweight reproductive-aged women, who do not have any co-existing co-morbidities that require medication. WIDER IMPLICATIONS OF THE FINDINGS: Exercise, regardless of intensity, has clear health benefits for women with PCOS. HIIT appears to be a more beneficial strategy and should be considered for promoting health and reducing cardio-metabolic risk in overweight women with PCOS. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a Project Support Grant from the Australian National Health and Medical Research Council (NHMRC) Centre for Research Excellence in PCOS. The authors have no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: ACTRN12615000242527. TRIAL REGISTRATION DATE: 19 February 2015. DATE OF FIRST PATIENT'S ENROLMENT: 27 May 2016.


Subject(s)
High-Intensity Interval Training , Insulin Resistance , Polycystic Ovary Syndrome , Adult , Australia , Female , High-Intensity Interval Training/methods , Humans , Overweight/complications , Overweight/therapy , Polycystic Ovary Syndrome/complications , Polycystic Ovary Syndrome/therapy
8.
J Mol Endocrinol ; 68(3): R11-R23, 2022 03 01.
Article in English | MEDLINE | ID: mdl-35060480

ABSTRACT

Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting pre-menopausal women and involves metabolic dysregulation. Despite the high prevalence of insulin resistance, the existence of mitochondrial dysregulation and its role in the pathogenesis of PCOS is not clear. Exercise is recommended as the first-line therapy for women with PCOS. In particular, high-intensity interval training (HIIT) is known to improve metabolic health and enhance mitochondrial characteristics. In this narrative review, the existing knowledge of mitochondrial characteristics in skeletal muscle and adipose tissue of women with PCOS and the effect of exercise interventions in ameliorating metabolic and mitochondrial health in these women are discussed. Even though the evidence on mitochondrial dysfunction in PCOS is limited, some studies point to aberrant mitochondrial functions mostly in skeletal muscle, while there is very little research in adipose tissue. Although most exercise intervention studies in PCOS report improvements in metabolic health, they show diverse and inconclusive findings in relation to mitochondrial characteristics. A limitation of the current study is the lack of comprehensive mitochondrial analyses and the diversity in exercise modalities, with only one study investigating the impact of HIIT alone. Therefore, further comprehensive large-scale exercise intervention studies are required to understand the association between metabolic dysfunction and aberrant mitochondrial profile, and the molecular mechanisms underlying the exercise-induced metabolic adaptations in women with PCOS.


Subject(s)
Insulin Resistance , Polycystic Ovary Syndrome , Adipose Tissue/metabolism , Exercise/physiology , Female , Humans , Insulin Resistance/physiology , Mitochondria/metabolism , Polycystic Ovary Syndrome/metabolism , Polycystic Ovary Syndrome/therapy
9.
Mol Metab ; 55: 101413, 2022 01.
Article in English | MEDLINE | ID: mdl-34890851

ABSTRACT

OBJECTIVES: Loss of functional ß-cell mass is a key factor contributing to poor glycemic control in advanced type 2 diabetes (T2D). We have previously reported that the inhibition of the neuropeptide Y1 receptor improves the islet transplantation outcome in type 1 diabetes (T1D). The aim of this study was to identify the pathophysiological role of the neuropeptide Y (NPY) system in human T2D and further evaluate the therapeutic potential of using the Y1 receptor antagonist BIBO3304 to improve ß-cell function and survival in T2D. METHODS: The gene expression of the NPY system in human islets from nondiabetic subjects and subjects with T2D was determined and correlated with the stimulation index. The glucose-lowering and ß-cell-protective effects of BIBO3304, a selective orally bioavailable Y1 receptor antagonist, in high-fat diet (HFD)/multiple low-dose streptozotocin (STZ)-induced and genetically obese (db/db) T2D mouse models were assessed. RESULTS: In this study, we identified a more than 2-fold increase in NPY1R and its ligand, NPY mRNA expression in human islets from subjects with T2D, which was significantly associated with reduced insulin secretion. Consistently, the pharmacological inhibition of Y1 receptors by BIBO3304 significantly protected ß cells from dysfunction and death under multiple diabetogenic conditions in islets. In a preclinical study, we demonstrated that the inhibition of Y1 receptors by BIBO3304 led to reduced adiposity and enhanced insulin action in the skeletal muscle. Importantly, the Y1 receptor antagonist BIBO3304 treatment also improved ß-cell function and preserved functional ß-cell mass, thereby resulting in better glycemic control in both HFD/multiple low-dose STZ-induced and db/db T2D mice. CONCLUSIONS: Our results revealed a novel causal link between increased islet NPY-Y1 receptor gene expression and ß-cell dysfunction and failure in human T2D, contributing to the understanding of the pathophysiology of T2D. Furthermore, our results demonstrate that the inhibition of the Y1 receptor by BIBO3304 represents a potential ß-cell-protective therapy for improving functional ß-cell mass and glycemic control in T2D.


Subject(s)
Insulin-Secreting Cells/physiology , Receptors, Neuropeptide Y/metabolism , Animals , Arginine/analogs & derivatives , Arginine/pharmacology , Diabetes Mellitus, Type 2/metabolism , Glucose/metabolism , Glycemic Control/methods , Insulin/metabolism , Male , Mice , Mice, Inbred C57BL , Neuropeptide Y/metabolism , Obesity/metabolism , Receptors, Neuropeptide Y/antagonists & inhibitors , Receptors, Neuropeptide Y/genetics
10.
BMC Public Health ; 21(1): 2310, 2021 12 20.
Article in English | MEDLINE | ID: mdl-34930180

ABSTRACT

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex condition, impacting cardio-metabolic and reproductive health, mental health and health-related quality of life. The physical health benefits of exercise for women with PCOS are well-established and exercise is increasingly being recognised as efficacious for improving psychological wellbeing. The aim of this review was to summarise the evidence regarding the effectiveness of exercise interventions on mental health outcomes in women with PCOS. METHODS: A systematic search of electronic databases was conducted in March of 2020. Trials that evaluated the effect of an exercise intervention on mental health or health-related quality of life outcomes in reproductive aged women with diagnosed PCOS were included. Methodological quality was assessed using the modified Downs and Black checklist. Primary outcomes included symptoms of depression and anxiety, and health-related quality of life. RESULTS: Fifteen articles from 11 trials were identified and deemed eligible for inclusion. Exercise demonstrated positive improvements in health-related quality of life in all of the included studies. Half of included studies also reported significant improvements in depression and anxiety symptoms. There was large variation in methodological quality of included studies and in the interventions utilised. CONCLUSIONS: The available evidence indicates that exercise is effective for improving health-related quality of life and PCOS symptom distress. Exercise also shows some efficacy for improving symptoms and/or prevalence of depression and anxiety in women with PCOS. However, due to large heterogeneity of included studies, conclusions could not be made regarding the impact of exercise intervention characteristics. High-quality trials with well reported exercise intervention characteristics and outcomes are required in order to determine effective exercise protocols for women with PCOS and facilitate translation into practice.


Subject(s)
Polycystic Ovary Syndrome , Adult , Anxiety/epidemiology , Anxiety/therapy , Depression/epidemiology , Depression/therapy , Exercise Therapy , Female , Humans , Mental Health , Polycystic Ovary Syndrome/epidemiology , Polycystic Ovary Syndrome/psychology , Polycystic Ovary Syndrome/therapy , Quality of Life
11.
J Mol Endocrinol ; 68(1): 63-76, 2021 12 03.
Article in English | MEDLINE | ID: mdl-34752415

ABSTRACT

Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with insulin resistance and impaired energy metabolism in skeletal muscle, the aetiology of which is currently unclear. Here, we mapped the gene expression profile of skeletal muscle from women with PCOS and determined if cultured primary myotubes retain the gene expression signature of PCOS in vivo. Transcriptomic analysis of vastus lateralis biopsies collected from PCOS women showed lower expression of genes associated with mitochondrial function, while the expression of genes associated with the extracellular matrix was higher compared to controls. Altered skeletal muscle mRNA expression of mitochondrial-associated genes in PCOS was associated with lower protein expression of mitochondrial complex II-V, but not complex I, with no difference in mitochondrial DNA content. Transcriptomic analysis of primary myotube cultures established from biopsies did not display any differentially expressed genes between controls and PCOS. Comparison of gene expression profiles in skeletal muscle biopsies and primary myotube cultures showed lower expression of mitochondrial and energy metabolism-related genes in vitro, irrespective of the group. Together, our results show that the altered mitochondrial-associated gene expression in skeletal muscle in PCOS is not preserved in cultured myotubes, indicating that the in vivo extracellular milieu, rather than genetic or epigenetic factors, may drive this alteration. Dysregulation of mitochondrial-associated genes in skeletal muscle by extracellular factors may contribute to the impaired energy metabolism associated with PCOS.


Subject(s)
Disease Susceptibility , Gene Expression Regulation , Genes, Mitochondrial , Mitochondria/genetics , Mitochondria/metabolism , Polycystic Ovary Syndrome/etiology , Polycystic Ovary Syndrome/metabolism , Biomarkers , Cells, Cultured , Cluster Analysis , Computational Biology/methods , DNA Copy Number Variations , Female , Gene Expression Profiling , Glucose/metabolism , Humans , Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/metabolism , Polycystic Ovary Syndrome/pathology , Transcriptome
12.
Front Endocrinol (Lausanne) ; 12: 732338, 2021.
Article in English | MEDLINE | ID: mdl-34707569

ABSTRACT

Women with polycystic ovary syndrome (PCOS), commonly have profound skeletal muscle insulin resistance which can worsen other clinical features. The heterogeneity of the condition has made it challenging to identify the precise mechanisms that cause this insulin resistance. A possible explanation for the underlying insulin resistance may be the dysregulation of Transforming Growth Factor-beta (TGFß) signalling. TGFß signalling contributes to the remodelling of reproductive and hepatic tissues in women with PCOS. Given the systemic nature of TGFß signalling and its role in skeletal muscle homeostasis, it may be possible that these adverse effects extend to other peripheral tissues. We aimed to determine if TGFß1 could negatively regulate glucose uptake and insulin signalling in skeletal muscle of women with PCOS. We show that both myotubes from women with PCOS and healthy women displayed an increase in glucose uptake, independent of changes in insulin signalling, following short term (16 hr) TGFß1 treatment. This increase occurred despite pro-fibrotic signalling increasing via SMAD3 and connective tissue growth factor in both groups following treatment with TGFß1. Collectively, our findings show that short-term treatment with TGFß1 does not appear to influence insulin signalling or promote insulin resistance in myotubes. These findings suggest that aberrant TGFß signalling is unlikely to directly contribute to skeletal muscle insulin resistance in women with PCOS in the short term but does not rule out indirect or longer-term effects.


Subject(s)
Glucose/pharmacokinetics , Insulin/metabolism , Muscle Fibers, Skeletal/drug effects , Polycystic Ovary Syndrome/metabolism , Transforming Growth Factor beta1/pharmacology , Adolescent , Adult , Carbohydrate Metabolism/drug effects , Case-Control Studies , Cells, Cultured , Female , Glucose/metabolism , Glucose Clamp Technique , Humans , Insulin Resistance/physiology , Middle Aged , Muscle Fibers, Skeletal/metabolism , Muscle Fibers, Skeletal/pathology , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Polycystic Ovary Syndrome/pathology , Signal Transduction/drug effects , Transforming Growth Factor beta1/physiology , Young Adult
13.
JMIR Res Protoc ; 10(4): e18777, 2021 Apr 09.
Article in English | MEDLINE | ID: mdl-33835038

ABSTRACT

BACKGROUND: Bone and muscle are closely linked anatomically, biochemically, and metabolically. Acute exercise affects both bone and muscle, implying a crosstalk between the two systems. However, how these two systems communicate is still largely unknown. We will explore the role of undercarboxylated osteocalcin (ucOC) in this crosstalk. ucOC is involved in glucose metabolism and has a potential role in muscle maintenance and metabolism. OBJECTIVE: The proposed trial will determine if circulating ucOC levels in older adults at baseline and following acute exercise are associated with parameters of muscle function and if the ucOC response to exercise varies between older adults with low muscle quality and those with normal or high muscle quality. METHODS: A total of 54 men and women aged 60 years or older with no history of diabetes and warfarin and vitamin K use will be recruited. Screening tests will be performed, including those for functional, anthropometric, and clinical presentation. On the basis of muscle quality, a combined equation of lean mass (leg appendicular skeletal muscle mass in kg) and strength (leg press; one-repetition maximum), participants will be stratified into a high or low muscle function group and randomized into the controlled crossover acute intervention. Three visits will be performed approximately 7 days apart, and acute aerobic exercise, acute resistance exercise, and a control session (rest) will be completed in any order. Our primary outcome for this study is the effect of acute exercise on ucOC in older adults with low muscle function and those with high muscle function. RESULTS: The trial is active and ongoing. Recruitment began in February 2018, and 38 participants have completed the study as of May 26, 2019. CONCLUSIONS: This study will provide novel insights into bone and muscle crosstalk in older adults, potentially identifying new clinical biomarkers and mechanistic targets for drug treatments for sarcopenia and other related musculoskeletal conditions. TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry ACTRN12618001756213; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375925. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/18777.

14.
Nutr Metab (Lond) ; 17: 68, 2020.
Article in English | MEDLINE | ID: mdl-32821265

ABSTRACT

BACKGROUND: Physical exercise and activity status may modify the effect of the fat mass- and obesity-associated (FTO) genotype on body weight and obesity risk. To understand the interaction between FTO's effect and physical activity, the present study investigated the effects of high and low intensity exercise on FTO mRNA and protein expression, and potential modifiers of exercise-induced changes in FTO in healthy-weighted individuals. METHODS: Twenty-eight untrained males and females (25.4 ± 1.1 years; 73.1 ± 2.0 kg; 178.8 ± 1.4 cm; 39.0 ± 1.2 ml.kg.min- 1 VO2peak) were genotyped for the FTO rs9939609 (T > A) polymorphism and performed isocaloric (400 kcal) cycle ergometer exercise on two separate occasions at different intensities: 80% (High Intensity (HI)) and 40% (Low Intensity (LO)) VO2peak. Skeletal muscle biopsies (vastus lateralis) and blood samples were taken pre-exercise and following 10 and 90 mins passive recovery. RESULTS: FTO mRNA expression was significantly decreased after HI intensity exercise (p = 0.003). No differences in basal and post-exercise FTO protein expression were evident between FTO genotypes. Phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and Akt substrate of 160 kDa (AS160) were significantly increased following HI intensity exercise (p < 0.05). Multivariate models of metabolomic data (orthogonal two partial least squares discriminant analysis (O2PLS-DA)) were unable to detect any significant metabolic differences between genotypes with either exercise trial (p > 0.05). However, skeletal muscle glucose accumulation at 10 mins following HI (p = 0.021) and LO (p = 0.033) intensity exercise was greater in AA genotypes compared to TT genotypes. CONCLUSION: Our novel data provides preliminary evidence regarding the effects of exercise on FTO expression in skeletal muscle. Specifically, high intensity exercise downregulates expression of FTO mRNA and suggests that in addition to nutritional regulation, FTO could also be regulated by exercise. TRIAL REGISTRATION: ACTRN12612001230842. Registered 21 November 2012 - Prospectively registered, https://www.anzctr.org.au/.

15.
J Clin Med ; 8(10)2019 Oct 03.
Article in English | MEDLINE | ID: mdl-31623391

ABSTRACT

Polycystic Ovary Syndrome (PCOS) is a complex condition with mechanisms likely to involve the interaction between genetics and lifestyle. Familial clustering of PCOS symptoms is well documented, providing evidence for a genetic contribution to the condition. This overview aims firstly to systematically summarise the current literature surrounding genetics and PCOS, and secondly, to assess the methodological quality of current systematic reviews and identify limitations. Four databases were searched to identify candidate gene systematic reviews, and quality was assessed with the AMSTAR tool. Genome-wide association studies (GWAS) were identified by a semi structured literature search. Of the candidate gene systematic reviews, 17 were of high to moderate quality and four were of low quality. A total of 19 gene loci have been associated with risk of PCOS in GWAS, and 11 of these have been replicated across two different ancestries. Gene loci were located in the neuroendocrine, metabolic, and reproductive pathways. Overall, the gene loci with the most robust findings were THADA, FSHR, INS-VNTR, and DENND1A, that now require validation. This overview also identified limitations of the current literature and important methodological considerations for future genetic studies. Much work remains to identify causal variants and functional relevance of genes associated with PCOS.

16.
J Clin Endocrinol Metab ; 104(12): 6155-6170, 2019 12 01.
Article in English | MEDLINE | ID: mdl-31390009

ABSTRACT

CONTEXT: Polycystic ovary syndrome (PCOS) is a chronic disease affecting reproductive function and whole-body metabolism. Although the etiology is unclear, emerging evidence indicates that the epigenetics may be a contributing factor. OBJECTIVE: To determine the role of global and genome-wide epigenetic modifications in specific immune cells in PCOS compared with controls and whether these could be related to clinical features of PCOS. DESIGN: Cross-sectional study. PARTICIPANTS: Women with (n = 17) or without PCOS (n = 17). SETTING: Recruited from the general community. MAIN OUTCOME MEASURES: Isolated peripheral blood mononuclear cells were analyzed using multicolor flow cytometry methods to determine global DNA methylation levels in a cell-specific fashion. Transcriptomic and genome-wide DNA methylation analyses were performed on T helper cells using RNA sequencing and reduced representation bisulfite sequencing. RESULTS: Women with PCOS had lower global DNA methylation in monocytes (P = 0.006) and in T helper (P = 0.004), T cytotoxic (P = 0.004), and B cells (P = 0.03). Specific genome-wide DNA methylation analysis of T helper cells from women with PCOS identified 5581 differentially methylated CpG sites. Functional gene ontology enrichment analysis showed that genes located at the proximity of differentially methylated CpG sites belong to pathways related to reproductive function and immune cell function. However, these genes were not altered at the transcriptomic level. CONCLUSIONS: It was shown that PCOS is associated with global and gene-specific DNA methylation remodeling in a cell type-specific manner. Further investigation is warranted to determine whether epigenetic reprogramming of immune cells is important in determining the different phenotypes of PCOS.


Subject(s)
Epigenesis, Genetic/physiology , Leukocytes, Mononuclear/metabolism , Lymphocytes/metabolism , Polycystic Ovary Syndrome/genetics , Polycystic Ovary Syndrome/immunology , Reproduction/genetics , Adolescent , Adult , Case-Control Studies , Cellular Reprogramming/genetics , Cellular Reprogramming/immunology , Cross-Sectional Studies , DNA Methylation/physiology , Female , Genetic Predisposition to Disease , Humans , Immune System/metabolism , Infertility, Female/genetics , Infertility, Female/immunology , Middle Aged , Polycystic Ovary Syndrome/metabolism , Reproduction/immunology , Young Adult
17.
Sports Med ; 49(8): 1143-1157, 2019 08.
Article in English | MEDLINE | ID: mdl-31166000

ABSTRACT

In this opinion piece, we summarize, discuss implications of implementation, and critically evaluate our 2018 evidence-based guideline recommendations for exercise and physical activity in women with polycystic ovary syndrome (PCOS). We developed recommendations as part of a larger international guideline development project. The overall guideline scope and priorities were informed by extensive health professional and consumer engagement. The lifestyle guideline development group responsible for the exercise recommendations included experts in endocrinology, exercise physiology, gynecology, dietetics, and obstetrics, alongside consumers. Extensive online communications and two face-to-face meetings addressed five prioritized clinical questions related to lifestyle, including the role of exercise as therapy for women with PCOS. The guideline recommendations were formulated based on one narrative and two evidence-based reviews, before consensus voting within the guideline panel. The development process was in accordance with the Appraisal of Guidelines for Research and Evaluation (AGREE) II, and used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework to assess evidence quality, desirable and undesirable consequences, feasibility, acceptability, cost, implementation, and recommendation strength. Given the evidence for exercise as therapy in PCOS being of low quality, a consensus recommendation was made based on current exercise guidelines for the general population. Women with PCOS and clinicians are forced to adopt generic approaches when recommending exercise therapy that perpetuates clinical management with pharmacological solutions. The current status of evidence highlights the need for greater international co-operation between researchers and funding agencies to address key clinical knowledge gaps around exercise therapy in PCOS to generate evidence for appropriate, scalable, and sustainable best practice approaches.


Subject(s)
Exercise Therapy , Polycystic Ovary Syndrome/therapy , Consensus , Disease Management , Evidence-Based Medicine , Female , Humans , Meta-Analysis as Topic , Randomized Controlled Trials as Topic , Systematic Reviews as Topic
18.
Trials ; 20(1): 221, 2019 Apr 16.
Article in English | MEDLINE | ID: mdl-30992038

ABSTRACT

BACKGROUND: Polycystic ovary syndrome (PCOS) is a reproductive-metabolic condition. Insulin resistance is a hallmark of PCOS and is related to increased hyperandrogenism that drives inherent metabolic, reproductive and psychological features of the syndrome. Insulin resistance in women with PCOS is managed by weight loss, lifestyle interventions (i.e. exercise, diet) and insulin-sensitising medications. This manuscript describes the protocol of our study evaluating the effectiveness of high intensity intermittent training (HIIT) or moderate intensity exercise on cardiometabolic, reproductive and mental health in overweight women with PCOS. METHODS/DESIGN: We will employ a three arm, parallel-group, randomised controlled trial recruiting 60 women diagnosed with PCOS, aged between 18 and 45 years and with a body mass index (BMI) greater than 25 kg/m2. Following screening and baseline testing, women will be randomised by simple randomisation procedure using computer generated sequence allocation to undergo one of two 12-week supervised interventions: either HIIT or moderate intensity exercise (standard supervised exercise), or to standard care [Con] (unsupervised lifestyle advice) at a 1:1:1 allocation ratio. The primary outcome for this trial is to measure the improvements in metabolic health; specifically changes in insulin sensitivity in response to different exercise intensities. Baseline and post-intervention testing include anthropometric measurements, cardiorespiratory fitness testing, reproductive hormone profiles (anti-müllerian hormone and steroid profiles), metabolic health, health-related quality of life and mental health questionnaires and objective and subjective lifestyle monitoring. Reporting of the study will follow the CONSORT statement. DISCUSSION: This trial aims to demonstrate the comparative efficacy and maintenance of different exercise intensities to advance the understanding of PCOS management and provide insight into the optimal exercise intensity for improved cardiometabolic outcomes. Secondary outcomes will include the impact of different exercise protocols on reproductive hormone profiles, mental health and health-related quality of life. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12615000242527 . Registered on 17 March 2015.


Subject(s)
Exercise Therapy/methods , Mental Health , Polycystic Ovary Syndrome/therapy , Randomized Controlled Trials as Topic , Reproductive Health , Adolescent , Adult , Female , Humans , Insulin Resistance , Middle Aged , Outcome Assessment, Health Care , Polycystic Ovary Syndrome/metabolism , Polycystic Ovary Syndrome/psychology , Quality of Life , Sample Size , Young Adult
19.
J Clin Endocrinol Metab ; 104(11): 5372-5381, 2019 11 01.
Article in English | MEDLINE | ID: mdl-30938770

ABSTRACT

CONTEXT: Polycystic ovary syndrome (PCOS) is a common endocrine condition affecting 8% to 13% of women across the lifespan. PCOS affects reproductive, metabolic, and mental health, generating a considerable health burden. Advances in treatment of women with PCOS has been hampered by evolving diagnostic criteria and poor recognition by clinicians. This has resulted in limited clinical and basic research. In this study, we provide insights into the current and future research on the metabolic features of PCOS, specifically as they relate to PCOS-specific insulin resistance (IR), that may affect the most metabolically active tissue, skeletal muscle. CURRENT KNOWLEDGE: PCOS is a highly heritable condition, yet it is phenotypically heterogeneous in both reproductive and metabolic features. Human studies thus far have not identified molecular mechanisms of PCOS-specific IR in skeletal muscle. However, recent research has provided new insights that implicate energy-sensing pathways regulated via epigenomic and resultant transcriptomic changes. Animal models, while in existence, have been underused in exploring molecular mechanisms of IR in PCOS and specifically in skeletal muscle. FUTURE DIRECTIONS: Based on the latest evidence synthesis and technologies, researchers exploring molecular mechanisms of IR in PCOS, specifically in muscle, will likely need to generate new hypothesis to be tested in human and animal studies. CONCLUSION: Investigations to elucidate the molecular mechanisms driving IR in PCOS are in their early stages, yet remarkable advances have been made in skeletal muscle. Overall, investigations have thus far created more questions than answers, which provide new opportunities to study complex endocrine conditions.


Subject(s)
Insulin Resistance , Muscle, Skeletal/metabolism , Polycystic Ovary Syndrome/metabolism , Animals , Disease Models, Animal , Female , Humans , Signal Transduction
20.
Diabetes ; 66(12): 3029-3040, 2017 12.
Article in English | MEDLINE | ID: mdl-28970284

ABSTRACT

The pancreatic ß-cell transcriptome is highly sensitive to external signals such as glucose oscillations and stress cues. MicroRNAs (miRNAs) have emerged as key factors in gene expression regulation. Here, we aimed to identify miRNAs that are modulated by glucose in mouse pancreatic islets. We identified miR-708 as the most upregulated miRNA in islets cultured at low glucose concentrations, a setting that triggers a strong stress response. miR-708 was also potently upregulated by triggering endoplasmic reticulum (ER) stress with thapsigargin and in islets of ob/ob mice. Low-glucose induction of miR-708 was blocked by treatment with the chemical chaperone 4-phenylbutyrate, uncovering the involvement of ER stress in this response. An integrative analysis identified neuronatin (Nnat) as a potential glucose-regulated target of miR-708. Indeed, Nnat expression was inversely correlated with miR-708 in islets cultured at different glucose concentrations and in ob/ob mouse islets and was reduced after miR-708 overexpression. Consistent with the role of Nnat in the secretory function of ß-cells, miR-708 overexpression impaired glucose-stimulated insulin secretion (GSIS), which was recovered by NNAT overexpression. Moreover, miR-708 inhibition recovered GSIS in islets cultured at low glucose. Finally, miR-708 overexpression suppressed ß-cell proliferation and induced ß-cell apoptosis. Collectively, our results provide a novel mechanism of glucose regulation of ß-cell function and growth by repressing stress-induced miR-708.


Subject(s)
Endoplasmic Reticulum Stress , Insulin-Secreting Cells/physiology , MicroRNAs/physiology , Animals , Apoptosis , Cells, Cultured , Insulin-Secreting Cells/metabolism , Male , Membrane Proteins/analysis , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Obese , MicroRNAs/analysis , Nerve Tissue Proteins/analysis , Transcription Factor CHOP/genetics
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