Interrupting Prolonged Sitting and Endothelial Function in Polycystic Ovary Syndrome

The Role of Lifestyle Interventions in PCOS Management: A Systematic Review

Polycystic ovary syndrome (PCOS) is one of the most prevalent endocrine disorders among reproductive-aged women. It is characterized by hyperandrogenism, anovulation, and polycystic ovaries. Lifestyle changes are suggested as first-line interventions in managing PCOS. This systematic review aims to assess the scientific evidence regarding the role of lifestyle modifications (dietary changes, physical activity, and behavioral changes) in improving reproductive, anthropometric, metabolic, and psychological outcomes in women with PCOS. Dietary interventions such as foods with low glycemic index scores; caloric restrictions; high-fiber, omega three fatty acid-rich diets; ketogenic diets; Mediterranean diets; antioxidant-rich food; and anti-inflammatory diets improve insulin sensitivity and hormonal balance in women with PCOS. Physical activity, like aerobic and resistance exercise, enhances insulin sensitivity, helps weight loss, and improves metabolic and reproductive outcomes in women with PCOS. Further, behavioral and education modules can also be used to improve awareness, adherence, and the effectiveness of conventional treatment and to manage mental health issues related to PCOS. Collectively, lifestyle modifications not only improve the biochemical, hormonal, and anthropometric parameters in PCOS patients but also reduce the long-term risks of metabolic and cardiovascular diseases.

24-hour movement behaviours and cardiometabolic markers in women with polycystic ovary syndrome (PCOS): a compositional data analysis

STUDY QUESTION

Are 24-h movement composition and time reallocations between the movement behaviours (moderate-to-vigorous physical activity (MVPA), light physical activity (LPA), sedentary behaviour (SB), and sleep) differentially associated with cardiometabolic markers in women with polycystic ovary syndrome (PCOS) relative to women without PCOS?

SUMMARY ANSWER

There was no difference in 24-h movement composition between the groups, although among women without PCOS, reducing SB time while increasing either MVPA or LPA time was associated with beneficial differences in cardiometabolic markers, whereas in women with PCOS beneficial differences were observed only when SB time was replaced with MVPA.

WHAT IS KNOWN ALREADY

Women with PCOS display lower levels of physical activity, higher sedentary time, and less total sleep than women without the syndrome. Exercise interventions among women with PCOS have shown improvements in body composition and insulin sensitivity, while the findings regarding blood pressure, insulin resistance, and lipid profiles are contradictory.

STUDY DESIGN, SIZE, DURATION

This study was part of a prospective, general population-based Northern Finland Birth Cohort 1966 (NFBC1966) (n = 5889 women). At the 31-year and 46-year follow-up, data collection was performed through postal and clinical examinations, including fasting blood samples and anthropometric measurements. Accelerometer data collection of 14 days (n = 2602 women) and a 2-h oral glucose tolerance test (n = 2780 women) were performed at the 46-year follow-up. Participants were identified as women with or without PCOS at age 31 (n = 1883), and the final study population included those who provided valid accelerometer data at age 46 (n = 857).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women with PCOS (n = 192) were identified based on the 2023 International Evidence-based Guideline, while those who exhibited no PCOS features were considered women without PCOS (controls; n = 665). Accelerometer-measured MVPA, LPA, and SB were combined with self-reported sleep to obtain 24-h compositions. Multivariable regression analysis based on compositional data analysis and isotemporal reallocations were performed to investigate the associations between 24-h movement composition and cardiometabolic markers. Isotemporal reallocations were expressed as differences (%Δ) from the sample's mean.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no difference in overall 24-h movement composition between women with PCOS and controls in midlife. The 24-h movement composition was associated with waist circumference, triglycerides, fasting serum insulin, and Homeostatic Model Assessment-insulin resistance (HOMA-IR) in both controls and women with PCOS. Reallocating 15 min from SB to MVPA was associated with favourable differences in cardiometabolic markers in both controls (%Δ range from -1.7 to -4.9) and women with PCOS (%Δ range from -1.9 to -8.6). Reallocating 15 min from SB to LPA was also associated with favourable differences in cardiometabolic markers among controls (%Δ range from -0.5 to -1.6) but not among women with PCOS.

LIMITATIONS, REASONS FOR CAUTION

The substitution technique used in this study is theoretical, which can be considered as a limitation. Other limitations of this study are the use of self-reported sleeping time and the difference in the group sample sizes.

WIDER IMPLICATIONS OF THE FINDINGS

These findings suggest that women with PCOS should be targeted with interventions involving physical activity of at least moderate intensity to improve their cardiometabolic health and underline the importance of developing tailored activity guidelines for women with PCOS.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Jenny and Antti Wihuri Foundation, Sigrid Juselius Foundation, Novo Nordisk (NNF21OC0070372), Research Council of Finland (315921/2018, 321763/2019, 6GESS 336449), Ministry of Education and Culture of Finland (OKM/54/626/2019, OKM/85/626/2019, OKM/1096/626/2020, OKM/20/626/2022, OKM/76/626/2022, and OKM/68/626/2023), and Roche Diagnostics International Ltd. L.J.M. is supported by a Veski Fellowship. M.Nu. has received funding from Fibrobesity-project, a strategic profiling project at the University of Oulu, which is supported by Research Council of Finland (Profi6 336449). NFBC1966 follow-ups received financial support from University of Oulu (Grant no. 65354, 24000692), Oulu University Hospital (Grant no. 2/97, 8/97, 24301140), Ministry of Health and Social Affairs (Grant no. 23/251/97, 160/97, 190/97), National Institute for Health and Welfare, Helsinki (Grant no. 54121), Regional Institute of Occupational Health, Oulu, Finland (Grant no. 50621, 54231), and ERDF European Regional Development Fund (Grant no. 539/2010 A31592). T.T.P. declares consulting fees from Gedeon Richter, Organon, Astellas, Roche; speaker's fees from Gedeon Richter, Exeltis, Roche, Stragen, Merck, Organon; and travel support from Gedeon Richter. The remaining authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Effect of physical activity breaks during prolonged sitting on vascular outcomes: A scoping review

Emerging evidence claims the vascular benefits of varied frequency and duration of physical activity (PA) breaks, whereas the efficacy of varied intensity remains unexplored. We aimed to collate and summate the studies investigating the PA breaks at various intensities on vascular protection. Seven electronic databases were searched for potential studies till Jan 31, 2022. The eligible studies should have administered PA breaks of differing intensities in prolonged sitting postures and explored regional vascular changes [flow mediated dilation (FMD), shear stress, diameter, and blood flow] using ultrasound and novel outcome markers. Two independent reviewers assessed the studies for eligibility after abstract and full-text screen, and appropriate data were extracted to summarise vascular protective effects with PA breaks. Our findings reveal adverse regional vascular outcomes with prolonged sitting (FMD ≈ -1.5%, diameter ≈ -0.06 mm), whereas PA breaks of any intensity were found to improve endothelial functions (FMD ≈ +0.5%, diameter ≈ +0.1 mm, shear ≈ +13 s-1) and mitigate the adverse effects associated with prolonged sitting. Compared with high-intensity activity, low-intensity PA breaks alleviate arterial stiffness and endothelial dysfunction risks.

Acceptability of Performing Resistance Exercise Breaks in the Workplace to Break Up Prolonged Sedentary Time: A Randomized Control Trial in U.S. Office Workers and Students

We investigated the acceptability of bodyweight resistance exercise breaks (REB) to disrupt prolonged sedentary behavior in the workplace. Twenty-nine individuals completed a REB, where they performed 3-min REB 4, 8, and 16 times on days 1-2, 3-4, and 5 of the workweek, respectively, and a control condition (i.e., SIT). Productivity was assessed on days 1 and 5 each week. The acceptability of each REB frequency was assessed. When asked to complete 4, 8, and 16 REB, participants completed (mean values) 3.2, 6.2, and 9.2 REB/day, respectively. Moreover, 88%, 40%, and 9% of participants expressed that the 4-, 8-, and 16-REB frequencies were acceptable, respectively. Decision-making ability and concentration levels increased from day 1-5 of the REB week (p=0.048) but were stable during SIT. REB (4/day) are highly acceptable and could be a promising intervention strategy for reducing occupational sitting, thus decreasing sedentary-behavior-induced risk.

Physiology of sedentary behavior

Sedentary behaviors (SB) are characterized by low energy expenditure while in a sitting or reclining posture. Evidence relevant to understanding the physiology of SB can be derived from studies employing several experimental models: bed rest, immobilization, reduced step count, and reducing/interrupting prolonged SB. We examine the relevant physiological evidence relating to body weight and energy balance, intermediary metabolism, cardiovascular and respiratory systems, the musculoskeletal system, the central nervous system, and immunity and inflammatory responses. Excessive and prolonged SB can lead to insulin resistance, vascular dysfunction, shift in substrate use toward carbohydrate oxidation, shift in muscle fiber from oxidative to glycolytic type, reduced cardiorespiratory fitness, loss of muscle mass and strength and bone mass, and increased total body fat mass and visceral fat depot, blood lipid concentrations, and inflammation. Despite marked differences across individual studies, longer term interventions aimed at reducing/interrupting SB have resulted in small, albeit marginally clinically meaningful, benefits on body weight, waist circumference, percent body fat, fasting glucose, insulin, HbA1c and HDL concentrations, systolic blood pressure, and vascular function in adults and older adults. There is more limited evidence for other health-related outcomes and physiological systems and for children and adolescents. Future research should focus on the investigation of molecular and cellular mechanisms underpinning adaptations to increasing and reducing/interrupting SB and the necessary changes in SB and physical activity to impact physiological systems and overall health in diverse population groups.

Association between self-reported sedentary behavior and health-related quality of life among infertile women with polycystic ovary syndrome

BACKGROUND

High sedentary behavior and poor health-related quality of life (HRQoL) were common among women with polycystic ovary syndrome (PCOS). However, the association of sedentary behavior with HRQoL among infertile women with PCOS is still unknown. This study aimed to investigate the association of sedentary behavior with HRQoL among them.

METHODS

A cross-sectional study was conducted with 283 participants recruited from infertility outpatient clinic. A self-administered, structured questionnaire including the modified PCOS health-related QoL questionnaire (MPCOSQ), the International Physical Activity Questionnaire short form (IPAQ-SF), the Patient Health Questionnaire-9 (PHQ-9), and the Generalized Anxiety Disorder-7 (GAD-7) was used. Anthropometric and laboratory indictors related to PCOS were also collected. Multivariable linear regression analyses were performed to identify the associations. Bonferroni correction was utilized for multiple testing correction.

RESULTS

Sedentary behavior was associated with reduced HRQoL among this group. Specifically, over seven hours per day of sedentary behavior was strongly associated with total and several aspects of HRQoL (β ranged from - 0.378 to - 0.141, all P < 0.0063) after adjusting for physical activity, anxiety and depression. In addition, elevated BMI (β = - 0.407, P < 0.001) and anxiety (β ranged from - 0.410 to - 0.245, all P < 0.0063) were associated with poor HRQoL, while physical activity and depression were not.

CONCLUSION

Sedentary behavior is an important behavior among infertile women with PCOS as it was associated with poorer HRQoL. Future interventions seeking to improve HRQoL should be considered to reduce sedentary behavior and psychological burden as primary intervention targets.

Screening of Active Ingredients from Wendan Decoction in Alleviating Palmitic Acid-Induced Endothelial Cell Injury

(1) Objective: Traditional Chinese medicine (TCM) plays an important role in the treatment of numerous illnesses. As a classic Chinese medicine, Wendan Decoction (WDD) encompasses a marvelous impact on the remedy of hyperlipidemia. It is known that hyperlipidemia leads to cardiovascular injury, therefore anti-vascular endothelial cell injury (AVECI) may be an underlying molecular mechanism of WDD in the cure of hyperlipidemia. However, there is no relevant research on the effect of WDD on vascular endothelial cells and its pharmacodynamic substances. Therefore, the purpose of this study was to investigate the protective effect of WDD on vascular endothelial cells. (2) Methods: The chemical constituents of WDD were determined by LC-MS/MS technology. The protective effects of 16 batches of WDD on samples from human umbilical vein endothelial cells (HUVECs) were evaluated. Finally, gray relation analysis (GRA) and partial least squares regression (PLSR) were used to analyze the potential correlation between chemical ingredients and AVECI. (3) Results: The results indicated that WDD had apparent protective effect on endothelial cells, and pharmacological properties in 16 batches of WDD tests were apparently discrepant. The GRA and PLSR showed that trigonelline, liquiritin, hesperidin, hesperetin, scopoletin, morin, quercetin, isoliquiritigenin, liquiritigenin and formononetin may be the active ingredients of AVECI in WDD. (4) Conclusions: WDD has a protective effect on endothelial cell injury induced by palmitic acid, which may be related to its component content. This method was suitable for the search of active components in classical TCM.

Detrimental effects of physical inactivity on peripheral and brain vasculature in humans: Insights into mechanisms, long-term health consequences and protective strategies

The growing prevalence of physical inactivity in the population highlights the urgent need for a more comprehensive understanding of how sedentary behaviour affects health, the mechanisms involved and what strategies are effective in counteracting its negative effects. Physical inactivity is an independent risk factor for different pathologies including atherosclerosis, hypertension and cardiovascular disease. It is known to progressively lead to reduced life expectancy and quality of life, and it is the fourth leading risk factor for mortality worldwide. Recent evidence indicates that uninterrupted prolonged sitting and short-term inactivity periods impair endothelial function (measured by flow-mediated dilation) and induce arterial structural alterations, predominantly in the lower body vasculature. Similar effects may occur in the cerebral vasculature, with recent evidence showing impairments in cerebral blood flow following prolonged sitting. The precise molecular and physiological mechanisms underlying inactivity-induced vascular dysfunction in humans are yet to be fully established, although evidence to date indicates that it may involve modulation of shear stress, inflammatory and vascular biomarkers. Despite the steady increase in sedentarism in our societies, only a few intervention strategies have been investigated for their efficacy in counteracting the associated vascular impairments. The current review provides a comprehensive overview of the evidence linking acute and short-term physical inactivity to detrimental effects on peripheral, central and cerebral vascular health in humans. We further examine the underlying molecular and physiological mechanisms and attempt to link these to long-term consequences for cardiovascular health. Finally, we summarize and discuss the efficacy of lifestyle interventions in offsetting the negative consequences of physical inactivity.

Effect of sedentary behavior interventions on vascular function in adults: A systematic review and meta-analysis

Sedentary behavior (SB) results in hemodynamic alterations within the vasculature, leading to vascular dysfunction that may be attenuated by various interventions. This systematic review and meta-analysis examined the effect of SB interventions on vascular function in adults using seven databases searched on December 17, 2020. All types of SB interventions were included such as short- and long-term interventions (≥7 days) in participants aged ≥18 years. The pooled effect (mean difference) of intervention on three outcomes, namely, flow-mediated dilation (FMD), shear rate (SR), and pulse wave velocity (PWV), was evaluated using random effects meta-analyses. The revised Cochrane risk-of-bias tool for randomized trials was employed to assess the quality of the included studies. Twenty-six studies (21 short-term and six long-term interventions) involving 669 participants from eight countries were included. Evidence from meta-analysis showed that short-term interventions targeting SB improved FMD by 1.50% (95% confidence interval [CI] 1.00-1.99) and increased SR by 12.70 S^-1 (95% CI 7.86-17.54); no significant pooled effect was found for PWV. Long-term SB interventions resulted in a 0.93% increase in FMD (95% CI 0.25-1.62) and had no significant effect on PWV. Findings of this systematic review and meta-analysis suggest that both short- and long-term SB interventions improved FMD but had no effect on PWV. Short-term interventions had a greater effect in improving lower extremity arterial function. Further studies targeting long-term SB interventions on vascular function in adults are warranted.

Acute effects of interrupting prolonged sitting on vascular function in type 2 diabetes

In healthy and overweight/obese adults, interrupting prolonged sitting with activity bouts mitigates impairment in vascular function. However, it is unknown whether these benefits extend to those with type 2 diabetes (T2D), nor whether an optimal frequency of activity interruptions exist. We examined the acute effects on vascular function in T2D of interrupting prolonged sitting with simple resistance activities (SRA) at different frequencies. In a randomized crossover trial, 24 adults with T2D (35-70 yr) completed three 7-h conditions: 1) uninterrupted sitting (SIT), 2) sitting with 3-min bouts of SRA every 30 min (SRA3), and 3) sitting with 6 min bouts of SRA every 60 min (SRA6). Femoral artery flow-mediated dilation (FMD), resting shear rate, blood flow, and endothelin-1 were measured at 0, 1, 3.5, 4.5, and 6.5-7 h. Mean femoral artery FMD over 7 h was significantly higher in SRA3 (4.1 ± 0.3%) compared with SIT (3.7 ± 0.3%, P = 0.04) but not in SRA6. Mean resting femoral shear rate over 7 h was increased significantly for SRA3 (45.3 ± 4.1/s, P < 0.001) and SRA6 (46.2 ± 4.1/s, P < 0.001) relative to SIT (33.1 ± 4.1/s). Endothelin-1 concentrations were not statistically different between conditions. Interrupting sitting with activity breaks every 30 min, but not 60 min, significantly increased mean femoral artery FMD over 7 h, relative to SIT. Our findings suggest that more frequent and shorter breaks may be more beneficial than longer, less frequent breaks for vascular health in those with T2D.NEW & NOTEWORTHY This is the first trial to examine both the effects of interrupting prolonged sitting on vascular function in type 2 diabetes and the effects of the frequency and duration of interruptions. Brief, simple resistance activity bouts every 30 min, but not every 60 min, increased mean femoral artery flow-mediated dilation over 7 h, relative to uninterrupted sitting. With further supporting evidence, these initial findings can have important implications for cardiovascular health in type 2 diabetes.