Gender, sex hormones, and vascular tone

Effect of 5β-dihydrotestosterone on vasodilator function and on cell proliferation

Aging is one of the main factors associated with cardiovascular diseases. Androgens exert beneficial effects on the cardiovascular system and testosterone (TES) replacement therapy improves cardiometabolic risk factors. However, TES is contraindicated in patients with prostate cancer due to its proliferative effects on prostatic tumor cells. Additionally, TES and its reduced metabolites 5α- and 5β-dihydrotestosterone (5α-DHT and 5β-DHT) exert vasodilatory effects. Since androgen levels decrease during aging and 5β-DHT lacks genomic effects, this study is focused on analyzing its effect on vasodilator function and the proliferation rate of prostatic tumor and vascular smooth muscle cells. To study the vascular function, mesenteric arteries from aged-orchidectomized Sprague-Dawley rats were used. Mesenteric segments were divided into one control (without treatment) and three groups with the androgens (10 nM, 30 min) to analyze: acetylcholine- and sodium nitroprusside-induced responses and nitric oxide and superoxide anion production. To analyze cell proliferation, the effect of androgens on cell viability was determined. The results showed that 5β-DHT improves vasodilator function in arteries from aged-orchidectomized rats and induces antioxidant action, while the proliferation rate of the androgen-dependent prostatic tumor cells remains unaltered. These results make 5β-DHT a promising therapeutic agent for the treatment of cardiovascular pathologies.

Oral hormonal contraceptives and cardiovascular risks in females

Oral hormonal contraception (OHC) is a widely employed method in females for the prevention of unintended pregnancies, as well as for the treatment of menstrual disorders, endometriosis, and polycystic ovarian syndrome. However, it is believed that with OHCs use, some females may have higher risk of cardiovascular diseases, such as hypertension, diabetes, myocardial infarction, thrombosis, and heart failure. Although such risks are infrequently detected in healthy young females with the use of oral contraceptives, slightly elevated risks of cardiovascular diseases have been observed among reproductive-aged healthy females. However, prolonged use of OHC has also been claimed to have protective cardiac effects and may contribute to reduced risk of cardiovascular disease. In fact, the debate on whether OHC administration increases the risk of cardiovascular diseases has been ongoing with inconsistent and controversial viewpoints. Nevertheless, a great deal of work has been carried out to understand the relationship between OHC use and the occurrence of cardiovascular risk in females who use OHC for preventing the unwanted pregnancy or treatment of other disorders. Therefore, in this review we summarize the most recent available evidence regarding the association between the use of oral hormonal contraceptives and the risk for cardiovascular disease in females who are using OHC to prevent unintended pregnancy.

Sex differences in the epidemiology of spontaneous and traumatic cervical artery dissections

BACKGROUND

Recent studies show cervical artery dissection (CeAD) is equally common between sexes, and that the incidence of CeAD has risen at a greater rate in females than males. In this population-based study, we identify sex differences in patients diagnosed with spontaneous and traumatic CeAD.

METHODS

144 patients with spontaneous or traumatic CeAD were studied for sex differences in medical comorbidities, presenting symptoms and outcomes.

RESULTS

Females were more likely to carry a diagnosis of migraine, while males were more likely to have hyperlipidaemia. Females were more likely to present with neck pain, males with stroke. Females were significantly more likely to develop recurrent dissections in the study period.

CONCLUSIONS

These findings underscore the importance of understanding CeAD through the lens of sex differences and may explain the significant rise in the diagnosis of CeAD in females. These findings support the importance of considering sex-specific risk factors and medical comorbidities with sex predilection in the diagnosis and management of CeAD. Furthermore, it emphasises the importance of female patients understanding risk factors and presenting signs that should prompt evaluation for CeAD.

Beneficial Effects of Cocoa Flavanols on Microvascular Responses in Young Men May Be Dependent on Ethnicity and Lifestyle

Cocoa flavan-3-ols affect endothelium-dependent responses in resistance vessels and microcirculation has received little attention. We tested the effects of dark chocolate consumption (396 mg total flavanols/day for 3 days) in two Groups of 10 men (18-25 years; non-smokers) each comprising equal numbers of White European (WE) and South Asian (SA) ethnicity. In Group 1, dark chocolate did not affect reactive hyperaemia in forearm muscle, but augmented muscle dilatation evoked by acute mental stress, and reactive hyperaemia and acetylcholine (ACh)-evoked dilatation in cutaneous microcirculation. Conversely, in Group 2, chocolate did not affect cutaneous reactive hyperaemia or ACh-evoked dilatation, but these responses were blunted in Group 1 relative to Group 2. Further, when Groups 1 and 2 were combined, responses were blunted in SAs relative to WEs, augmented by chocolate in SAs only. In Group 2 individuals whose ACh-evoked dilatation was attenuated by nitric oxide synthase (NOS) inhibition, ACh-evoked dilatation was not altered after chocolate, but the attenuating effect of NOS inhibition was lost. Conversely, in Group 2 individuals whose ACh-evoked dilatation was enhanced by NOS inhibition, ACh-evoked dilatation was also augmented by chocolate. We propose that in resistance and microvessels of young men, cocoa flavan-3-ols preferentially augment endothelium-dependent dilator responses whose responses are depressed by familial and lifestyle factors more prevalent in SAs than Wes. Flavan-3-ols may facilitate the NOS pathway but also influence other endothelium-dependent dilators.

The Interaction of Vasopressin with Hormones of the Hypothalamo-Pituitary-Adrenal Axis: The Significance for Therapeutic Strategies in Cardiovascular and Metabolic Diseases

A large body of evidence indicates that vasopressin (AVP) and steroid hormones are frequently secreted together and closely cooperate in the regulation of blood pressure, metabolism, water-electrolyte balance, and behavior, thereby securing survival and the comfort of life. Vasopressin cooperates with hormones of the hypothalamo-pituitary-adrenal axis (HPA) at several levels through regulation of the release of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and multiple steroid hormones, as well as through interactions with steroids in the target organs. These interactions are facilitated by positive and negative feedback between specific components of the HPA. Altogether, AVP and the HPA cooperate closely as a coordinated functional AVP-HPA system. It has been shown that cooperation between AVP and steroid hormones may be affected by cellular stress combined with hypoxia, and by metabolic, cardiovascular, and respiratory disorders; neurogenic stress; and inflammation. Growing evidence indicates that central and peripheral interactions between AVP and steroid hormones are reprogrammed in cardiovascular and metabolic diseases and that these rearrangements exert either beneficial or harmful effects. The present review highlights specific mechanisms of the interactions between AVP and steroids at cellular and systemic levels and analyses the consequences of the inappropriate cooperation of various components of the AVP-HPA system for the pathogenesis of cardiovascular and metabolic diseases.

Cerebral and muscle tissue oxygenation during exercise in healthy adults: A systematic review

BACKGROUND

Near-infrared spectroscopy (NIRS) technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during exercise. Since this technology has been growing and is now successfully used in laboratory and sports settings, this systematic review aimed to synthesize the evidence and enhance an integrative understanding of blood flow adjustments and oxygen (O2) changes (i.e., the balance between O2 delivery and O2 consumption) within the cerebral and muscle systems during exercise.

METHODS

A systematic review was conducted using PubMed, Embase, Scopus, and Web of Science databases to search for relevant studies that simultaneously investigated cerebral and muscle hemodynamic changes using the near-infrared spectroscopy system during exercise. This review considered manuscripts written in English and available before February 9, 2023. Each step of screening involved evaluation by 2 independent authors, with disagreements resolved by a third author. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodological quality of the studies.

RESULTS

Twenty studies were included, of which 80% had good methodological quality, and involved 290 young or middle-aged adults. Different types of exercises were used to assess cerebral and muscle hemodynamic changes, such as cycling (n = 11), treadmill (n = 1), knee extension (n = 5), isometric contraction of biceps brachii (n = 3), and duet swim routines (n = 1). The cerebral hemodynamics analysis was focused on the frontal cortex (n = 20), while in the muscle, the analysis involved vastus lateralis (n = 18), gastrocnemius (n = 3), biceps brachii (n = 5), deltoid (n = 1), and intercostal muscle (n = 1). Overall, muscle deoxygenation increases during exercise, reaching a plateau in voluntary exhaustion, while in the brain, oxyhemoglobin concentration increases with exercise intensity, reaching a plateau or declining at the exhaustion point.

CONCLUSION

Muscle and cerebral oxygenation respond differently to exercise, with muscle increasing O2 utilization and cerebral tissue increasing O2 delivery during exercise. However, at the exhaustion point, both muscle and cerebral oxygenation become compromised. This is characterized by a reduction in blood flow and a decrease in O2 extraction in the muscle, while in the brain, oxygenation reaches a plateau or decline, potentially resulting in motor failure during exercise.

The beneficial roles and mechanisms of estrogens in immune health and infection disease

Multiple epidemiologic studies have revealed that gender is considered one of the important factors in the frequency and severity of certain infectious diseases, in which estrogens may play a vital role. There is growing evidence that estrogens as female sex hormone can modulate multiple biological functions outside of the reproductive system, such as in brain and cardiovascular system. However, it is largely unknown about the roles and mechanisms of estrogens/estrogen receptors in immune health and infection disease. Thence, by reading a lot of literature, we summarized the regulatory mechanisms of estrogens/estrogen receptors in immune cells and their roles in certain infectious diseases with gender differences. Therefore, estrogens may have therapeutic potentials to prevent and treat these infectious diseases, which needs further clinical investigation.

Recognition of Patient Gender: A Machine Learning Preliminary Analysis Using Heart Sounds from Children and Adolescents

Research has shown that X-rays and fundus images can classify gender, age group, and race, raising concerns about bias and fairness in medical AI applications. However, the potential for physiological sounds to classify sociodemographic traits has not been investigated. Exploring this gap is crucial for understanding the implications and ensuring fairness in the field of medical sound analysis. We aimed to develop classifiers to determine gender (men/women) based on heart sound recordings and using machine learning (ML). Data-driven ML analysis. We utilized the open-access CirCor DigiScope Phonocardiogram Dataset obtained from cardiac screening programs in Brazil. Volunteers < 21 years of age. Each participant completed a questionnaire and underwent a clinical examination, including electronic auscultation at four cardiac points: aortic (AV), mitral (MV), pulmonary (PV), and tricuspid (TV). We used Mel-frequency cepstral coefficients (MFCCs) to develop the ML classifiers. From each patient and from each auscultation sound recording, we extracted 10 MFCCs. In sensitivity analysis, we additionally extracted 20, 30, 40, and 50 MFCCs. The most effective gender classifier was developed using PV recordings (AUC ROC = 70.3%). The second best came from MV recordings (AUC ROC = 58.8%). AV and TV recordings produced classifiers with an AUC ROC of 56.4% and 56.1%, respectively. Using more MFCCs did not substantially improve the classifiers. It is possible to classify between males and females using phonocardiogram data. As health-related audio recordings become more prominent in ML applications, research is required to explore if these recordings contain signals that could distinguish sociodemographic features.

Association between the use of oral contraceptives and the occurrence of systemic hypertension: A systematic review with statistical comparison between randomized clinical trial interventions

Introduction

In the WHO eligibility criteria, there is agreement that hypertensive women taking Oral Contraceptive Hormonal Combined (OCHC) may be at increased risk of cardiovascular disease. The risk-to-benefit ratio hinges on the severity of the condition. While a mild increase in blood pressure is a common occurrence in consumers of OCHC, the potential for developing high blood pressure exists during oral contraceptive use. Consequently, there is a possibility of increased cardiovascular risk, with limited available data on this issue.

Objective

To evaluate the potential effects of OCHC on blood pressure through a systematic review with statistical analysis of existing randomized controlled trials.

Method

This systematic review with statistical comparison adheres to the recommendations outlined in the PRISMA (Principal Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The analysis strategy involves comparing the mean difference in blood pressure change according to the type of treatment, in addition to the calculation of clinically relevant outcomes (CRO).

Results

Our findings suggest a clinically relevant outcome related to the increase in blood pressure in users of ethinyl estradiol combined with gestodene in a cyclic regimen over 6 months. Conversely, a decrease in blood pressure was observed among users of ethinyl estradiol combined with chlormadinone over 24 months of usage.

Conclusion

While our study found minor variations in blood pressure across varying forms of oral contraceptives, these differences are not significant enough to warrant specific clinical recommendations. However, the results suggest that individuals with hypertension should exercise caution with ethinyl estradiol, particularly when administered cyclically alongside gestodene, due to the potential risk of increased blood pressure. Additionally, the use of oral contraceptives containing ethinyl estradiol paired with chlormadinone acetate or ethinyl estradiol combined with drospirenone may be more suitable for individuals at a high risk of developing hypertension.

Calcium signaling in endothelial and vascular smooth muscle cells: sex differences and the influence of estrogens and androgens

Calcium signaling in vascular endothelial cells (ECs) and smooth muscle cells (VSMCs) is essential for the regulation of vascular tone. However, the changes to intracellular Ca2+ concentrations are often influenced by sex differences. Furthermore, a large body of evidence shows that sex hormone imbalance leads to dysregulation of Ca2+ signaling and this is a key factor in the pathogenesis of cardiovascular diseases. In this review, the effects of estrogens and androgens on vascular calcium-handling proteins are discussed, with emphasis on the associated genomic or nongenomic molecular mechanisms. The experimental models from which data were collected were also considered. The review highlights 1) in female ECs, transient receptor potential vanilloid 4 (TRPV4) and mitochondrial Ca2+ uniporter (MCU) enhance Ca2+-dependent nitric oxide (NO) generation. In males, only transient receptor potential canonical 3 (TRPC3) plays a fundamental role in this effect. 2) Female VSMCs have lower cytosolic Ca2+ levels than males due to differences in the activity and expression of stromal interaction molecule 1 (STIM1), calcium release-activated calcium modulator 1 (Orai1), calcium voltage-gated channel subunit-α1C (CaV1.2), Na+-K+-2Cl- symporter (NKCC1), and the Na+/K+-ATPase. 3) When compared with androgens, the influence of estrogens on Ca2+ homeostasis, vascular tone, and incidence of vascular disease is better documented. 4) Many studies use supraphysiological concentrations of sex hormones, which may limit the physiological relevance of outcomes. 5) Sex-dependent differences in Ca2+ signaling mean both sexes ought to be included in experimental design.

Impact of Secondary Amenorrhea on Cardiovascular Disease Risk in Physically Active Women: A Systematic Review and Meta-Analysis

BACKGROUND

Exercise-associated secondary amenorrhea results in estrogen deficiency, which may lead to dysfunction in estrogen's normal cardioprotective pathways. Estrogen may be essential in a woman's endothelial adaptations to exercise. The objective of this review was to assess the association between secondary amenorrhea in physically active women and cardiovascular disease (CVD) risk.

METHODS AND RESULTS

A literature search was performed in January 2023 and updated in August 2023 of the Cumulative Index to Nursing and Allied Health Literature (EBSCOhost), Cochrane Library, Embase (Ovid), MEDLINE (Ovid), SPORTDiscus (EBSCOhost), and Scopus from inception to present with no date or language limitations. Citation chaining was done to screen for additional studies. Eight sources were searched for gray literature. Studies that compared physically active women with amenorrhea to physically active women with eumenorrhea aged 18 to 35 years with evidence of CVD, alterations to cardiovascular physiology, or CVD risks were included. Eighteen observational studies from 3 countries were included. Overall, the quality of evidence was good. A meta-analysis was performed. Physically active women with secondary amenorrhea had significantly lower estradiol, flow-mediated dilation, resting heart rate, systolic blood pressure, and diastolic blood pressure and higher total cholesterol, triglycerides, high-density lipoprotein, and low-density lipoprotein cholesterol.

CONCLUSIONS

Estrogen deficiency resulting from exercise-associated secondary amenorrhea in physically active women may impact cardiovascular physiology and certain CVD risk factors. The research in this area is observational; therefore, findings should be interpreted cautiously. However, as exercise-associated secondary amenorrhea is reversible and the primary prevention of CVD is important for public health, it may be important to treat secondary amenorrhea and restore estrogen levels.

Gender Influence on XOR Activities and Related Pathologies: A Narrative Review

Taking into account the patient's gender is the first step towards more precise and egalitarian medicine. The gender-related divergences observed in purine catabolism and their pathological consequences are good examples of gender medicine differences. Uric acid is produced by the activity of xanthine oxidoreductase (XOR). The serum levels of both XOR activity and uric acid differ physiologically between the genders, being higher in men than in women. Their higher levels have been associated with gout and hypertension, as well as with vascular, cardiac, renal, and metabolic diseases. The present review analyzes the gender-related differences in these pathological conditions in relation to increases in the serum levels of XOR and/or uric acid and the opportunity for gender-driven pharmacological treatment.

Testosterone modulates vasodilation in mesenteric arteries of hypertensive rats

AIMS

To evaluate the effects of testosterone on endothelium-dependent vasodilation and oxidative stress in mesenteric resistance arteries.

MAIN METHODS

Spontaneously hypertensive rats (SHR), aged 8 to 10 weeks, were divided into four groups: intact (SHAM), intact treated with testosterone (TTO; 3 mg/kg/day) via subcutaneous route (s.c.), intact treated with testosterone and anastrozole [aromatase enzyme inhibitor (TTO + ANA; 0.1 mg/kg/day, s.c.)] and intact treated with testosterone and finasteride [5 α-reductase enzyme inhibitor (TTO + FIN; 5 mg/kg/day, s.c.)] for four weeks. Concentration-response curves to acetylcholine (ACh, 0.1 nmol/L - 10 μmol/L) were obtained in mesenteric resistance arteries previously contracted with phenylephrine (PE, 3 μmol/L), before and after the use of selective inhibitors. Reactive oxygen species (ROS) levels were assessed in the vessels and the endothelium analyzed by scanning electron microscopy.

KEY FINDINGS

TTO group showed a lower participation of nitric oxide (NO), increased oxidative stress, and participation of prostanoids and endothelium-dependent hyperpolarization (EDH), possibly to maintain the vasodilator response. Lower participation of NO and prostanoids, combined to an increased participation of EDH, were observed in the TTO + ANA group, in addition to higher levels of ROS and altered endothelial morphology. The vasodilation to ACh was impaired in TTO + FIN, along increased participation of NO, reduction of prostanoids, and greater EDH-dependent vasodilation.

SIGNIFICANCE

Testosterone contributes to endothelial vasodilation by enhancing EDH through an increased participation of epoxyeicosatrienoic acids. While the decrease in NO appears to involve the participation of dihydrotestosterone, 17 β-estradiol seems to stimulate the action of the NO pathway and prostanoids.

Sex-Specific Acute Cerebrovascular Responses to Photothrombotic Stroke in Mice

Mechanisms underlying cerebrovascular stroke outcomes are poorly understood, and the effects of biological sex on cerebrovascular regulation post-stroke have yet to be fully comprehended. Here, we explore the overlapping roles of gonadal sex hormones and rho-kinase (ROCK), two important modulators of cerebrovascular tone, on the acute cerebrovascular response to photothrombotic (PT) focal ischemia in mice. Male mice were gonadectomized and female mice were ovariectomized to remove gonadal hormones, whereas control ("intact") animals received a sham surgery prior to stroke induction. Intact wild-type (WT) males showed a delayed drop in cerebral blood flow (CBF) compared with intact WT females, whereby maximal CBF drop was observed 48 h following stroke. Gonadectomy in males did not alter this response. However, ovariectomy in WT females produced a "male-like" phenotype. Intact Rock2+/- males also showed the same phenotypic response, which was not altered by gonadectomy. Alternatively, intact Rock2+/- females showed a significant difference in CBF values compared with intact WT females, displaying higher CBF values immediately post-stroke and showing a maximal CBF drop 48 h post-stroke. This pattern was not altered by ovariectomy. Altogether, these data illustrate sex differences in acute CBF responses to PT stroke, which seem to involve gonadal female sex hormones and ROCK2. Overall, this study provides a framework for exploring sex differences in acute CBF responses to focal ischemic stroke in mice.

An observational study of microcirculation among healthy individuals by age and sex

OBJECTIVE

This study measured normal ranges of microcirculatory parameters in healthy individuals and investigated differences in parameters by age and sex.

METHODS

Participants were enrolled into three groups with equal numbers of male and female: young (20-39 years), middle-aged (40-59 years), and elderly (60-79 years). Sublingual microcirculation images were obtained using the incident dark field (IDF).

RESULTS

A total of 75 female and 75 male healthy individuals were enrolled. The elderly group had a higher TVD (26.5 [2] vs. 25.2 [1.8]; p = 0.019) and a lower PPV (97 [2] vs. 98 [3]; p = 0.03) than did the young group. In the elderly group, systolic blood pressure (SBP) and mean arterial pressure (MAP) were moderately and positively correlated with MFI score (r = 0.407, p < 0.05, and r = 0.403, p < 0.05, respectively). The female participants had a lower MFI score than did the male participants (2.9 [2.8-3] vs. 3.0 [2.9-3]; p = 0.015).

CONCLUSIONS

This study revealed the range of microcirculatory parameters between different ages and sexes in healthy individuals. We found that blood pressure levels were correlated with microcirculatory parameters, especially in elders and female.

Basic Mechanisms of Brain Injury and Cognitive Decline in Hypertension

Dementia affects almost 50 million adults worldwide, and remains a major cause of death and disability. Hypertension is a leading risk factor for dementia, including Alzheimer disease and Alzheimer disease-related dementias. Although this association is well-established, the mechanisms underlying hypertension-induced cognitive decline remain poorly understood. By exploring the mechanisms mediating the detrimental effects of hypertension on the brain, studies have aimed to provide therapeutic insights and strategies on how to protect the brain from the effects of blood pressure elevation. In this review, we focus on the basic mechanisms contributing to the cerebrovascular adaptions to elevated blood pressure and hypertension-induced microvascular injury. We also assess the cellular mechanisms of neurovascular unit dysfunction, focusing on the premise that cognitive impairment ensues when the dynamic metabolic demands of neurons are not met due to neurovascular uncoupling, and summarize cognitive deficits across various rodent models of hypertension as a resource for investigators. Despite significant advances in antihypertensive therapy, hypertension remains a critical risk factor for cognitive decline, and several questions remain about the development and progression of hypertension-induced cognitive impairment.

In vitro cadmium exposure induces structural damage and endothelial dysfunction in female rat aorta

Cadmium is a heavy metal that is widespread in the environment and has been described as a metalloestrogen and a cardiovascular risk factor. Experimental studies conducted in male animals have shown that cadmium exposure induces vascular dysfunction, which could lead to vasculopathies caused by this metal. However, it is necessary to investigate the vascular effects of cadmium in female rats to understand its potential sex-dependent impact on the cardiovascular system. While its effects on male rats have been studied, cadmium may act differently in females due to its potential as a metalloestrogen. In vitro studies conducted in a controlled environment allow for a direct assessment of cadmium's impact on vascular function, and the use of female rats ensures that sex-dependent effects are evaluated. Therefore, the aim of this study was to investigate the in vitro effects of Cadmium Chloride (CdCl2, 5 µM) exposure on vascular reactivity in the isolated aorta of female Wistar rats. Exposure to CdCl2 damaged the architecture of the vascular endothelium. CdCl2 incubation increased the production and release of O2•-, reduced the participation of potassium (K+) channels, and increased the participation of the angiotensin II pathway in response to phenylephrine. Moreover, estrogen receptors alpha (Erα) modulated vascular reactivity to phenylephrine in the presence of cadmium, supporting the hypothesis that cadmium could act as a metalloestrogen. Our results demonstrated that in vitro cadmium exposure induces damage to endothelial architecture and an increase in oxidative stress in the isolated aorta of female rats, which could precipitate vasculopathies. Graphical Abstract. Own source from Canva and Servier Medical Art servers.

Burden of Hypertensive Heart Disease and High Systolic Blood Pressure in Australia from 1990 to 2019: Results From the Global Burden of Diseases Study

BACKGROUND

There is a dearth of comprehensive studies examining the burden and trends of hypertensive heart disease (HHD) and high systolic blood pressure (SBP) among the Australian population. We aimed to explore the burden of HHD and high SBP, and how they changed over time from 1990 to 2019 in Australia.

METHODS

We analysed data from the Global Burden of Disease study in Australia. We assessed the prevalence, mortality, disability-adjusted life-years (DALY), years lived with disability (YLD) and years of life lost (YLL) attributable to HHD and high SBP. Data were presented as point estimates with 95% uncertainty intervals (UI). We compared the burden of HHD and high SBP in Australia with World Bank defined high-income countries and six other comparator countries with similar sociodemographic characteristics and economies.

RESULTS

From 1990 to 2019, the burden of HHD and high SBP in Australia reduced. Age standardised prevalence rate of HHD was 119.3 cases per 100,000 people (95% UI 86.6-161.0) in 1990, compared to 80.1 cases (95% UI 57.4-108.1) in 2019. Deaths due to HDD were 3.4 cases per 100,000 population (95% UI 2.6-3.8) in 1990, compared to 2.5 (95% UI 1.9-3.0) in 2019. HHD contributed to 57.2 (95% UI 46.6-64.7) DALYs per 100,000 population in 1990 compared to 38.4 (95% UI 32.0-45.2) in 2019. Death rates per 100,000 population attributable to high SBP declined significantly over time for both sexes from 1990 (155.6 cases; 95% UI 131.2-177.0) to approximately one third in 2019 (53.8 cases; 95% UI 43.4-64.4). Compared to six other countries in 2019, the prevalence of HHD was highest in the USA (274.3%) and lowest in the UK (52.6%), with Australia displaying the third highest prevalence. Australia ranked second in term of lowest rates of deaths and third for lowest DALYs respectively due to high SBP. From 1990-2019, Australia ranked third best for reductions in deaths and DALYs due to HHD and first for reductions in deaths and DALYs due to high SBP.

CONCLUSION

Over the past three decades, the burden of HHD in Australia has reduced, but its prevalence remains relatively high. The contribution of high SBP to deaths, DALYs and YLLs also reduced over the three decades.

Neurovascular coupling and cerebrovascular hemodynamics are modified by exercise training status at different stages of maturation during youth

Neurovascular coupling (NVC) is mediated via nitric oxide signaling, which is independently influenced by sex hormones and exercise training. Whether exercise training differentially modifies NVC pre- versus postpuberty, where levels of circulating sex hormones will differ greatly within and between sexes, remains to be determined. Therefore, we investigated the influence of exercise training status on resting intracranial hemodynamics and NVC at different stages of maturation. Posterior and middle cerebral artery velocities (PCAv and MCAv) and pulsatility index (PCAPI and MCAPI) were assessed via transcranial Doppler ultrasound at rest and during visual NVC stimuli. N = 121 exercise-trained (males, n = 32; females, n = 32) and untrained (males, n = 28; females, n = 29) participants were characterized as pre (males, n = 33; females, n = 29)- or post (males, n = 27; females, n = 32)-peak height velocity (PHV). Exercise-trained youth demonstrated higher resting MCAv (P = 0.010). Maturity and training status did not affect the ΔPCAv and ΔMCAv during NVC. However, pre-PHV untrained males (19.4 ± 13.5 vs. 6.8 ± 6.0%; P ≤ 0.001) and females (19.3 ± 10.8 vs. 6.4 ± 7.1%; P ≤ 0.001) had a higher ΔPCAPI during NVC than post-PHV untrained counterparts, whereas the ΔPCAPI was similar in pre- and post-PHV trained youth. Pre-PHV untrained males (19.4 ± 13.5 vs. 7.9 ± 6.0%; P ≤ 0.001) and females (19.3 ± 10.8 vs. 11.1 ± 7.3%; P = 0.016) also had a larger ΔPCAPI than their pre-PHV trained counterparts during NVC, but the ΔPCAPI was similar in trained and untrained post-PHV youth. Collectively, our data indicate that exercise training elevates regional cerebral blood velocities during youth, but training-mediated adaptations in NVC are only attainable during early stages of adolescence. Therefore, childhood provides a unique opportunity for exercise-mediated adaptations in NVC.NEW & NOTEWORTHY We report that the change in cerebral blood velocity during a neurovascular coupling task (NVC) is similar in pre- and postpubertal youth, regardless of exercise-training status. However, prepubertal untrained youth demonstrated a greater increase in cerebral blood pulsatility during the NVC task when compared with their trained counterparts. Our findings highlight that childhood represents a unique opportunity for exercise-mediated adaptations in cerebrovascular hemodynamics during NVC, which may confer long-term benefits in cerebrovascular function.

Gender-based research underscores sex differences in biological processes, clinical disorders and pharmacological interventions

Earlier research has presumed that the male and female biology is similar in most organs except the reproductive system, leading to major misconceptions in research interpretations and clinical implications, with serious disorders being overlooked or misdiagnosed. Careful research has now identified sex differences in the cardiovascular, renal, endocrine, gastrointestinal, immune, nervous, and musculoskeletal systems. Also, several cardiovascular, immunological, and neurological disorders have shown differences in prevalence and severity between males and females. Genetic variations in the sex chromosomes have been implicated in several disorders at young age and before puberty. The levels of the gonadal hormones estrogen, progesterone and testosterone and their receptors play a role in the sex differences between adult males and premenopausal women. Hormonal deficiencies and cell senescence have been implicated in differences between postmenopausal and premenopausal women. Specifically, cardiovascular disorders are more common in adult men vs premenopausal women, but the trend is reversed with age with the incidence being greater in postmenopausal women than age-matched men. Gender-specific disorders in females such as polycystic ovary syndrome, hypertension-in-pregnancy and gestational diabetes have attained further research recognition. Other gender-related research areas include menopausal hormone therapy, the "Estrogen Paradox" in pulmonary arterial hypertension being more predominant but less severe in young females, and how testosterone may cause deleterious effects in the kidney while having vasodilator effects in the coronary circulation. This has prompted the National Institutes of Health (NIH) initiative to consider sex as a biological variable in research. The NIH and other funding agencies have provided resources to establish state-of-the-art centers for women health and sex differences in biology and disease in several academic institutions. Scientific societies and journals have taken similar steps to organize specialized conferences and publish special issues on gender-based research. These combined efforts should promote research to enhance our understanding of the sex differences in biological systems beyond just the reproductive system, and provide better guidance and pharmacological tools for the management of various clinical disorders in a gender-specific manner.

Experience of general anesthesia in a patient with menstrual-associated coronary spasm

Coronary angina due to low estrogen is relatively common around menopause, with almost no reports associated with the menstrual cycle or anesthetic management at younger ages. The patient was a 22-year-old woman who had developed ventricular fibrillation due to coronary spasm, resulting in cardiopulmonary arrest. She was resuscitated, and underwent ICD implantation. As her symptoms appeared at specific times during her menstrual cycle, she was diagnosed as having menstrual-associated coronary spasm, and started taking estrogen/progesterone medication. An endometrial ablation was scheduled for endometrial hyperplasia that was caused by the medicine. The surgery was scheduled in consideration of the patient's menstrual cycle, and general anesthesia was selected as the method of anesthesia. The surgery and perioperative management were uneventful, and her postoperative course was favorable. Our case is the first to our knowledge of general anesthesia performed on a patient with menstrual-associated coronary spasm.

Sex hormones impact early maturation and immune response in the arteriovenous fistula mouse model

Arteriovenous fistulae (AVF) fail to mature more frequently in female patients compared with male patients, leading to inferior outcomes and decreased utilization. Since our mouse AVF model recapitulates sex differences in human AVF maturation, we hypothesized that sex hormones mediate these differences during AVF maturation. C57BL/6 mice (9-11 wk) were treated with aortocaval AVF surgery and/or gonadectomy. AVF hemodynamics were measured via ultrasound (days 0-21). Blood was collected for FACS and tissue for immunofluorescence and ELISA (days 3 and 7); wall thickness was assessed by histology (day 21). Inferior vena cava shear stress was higher in male mice (P = 0.0028) after gonadectomy, and they had increased wall thickness (22.0 ± 1.8 vs. 12.7 ± 1.2 µm; P < 0.0001). Conversely, female mice had decreased wall thickness (6.8 ± 0.6 vs. 15.3 ± 0.9 µm; P = 0.0002). Intact female mice had higher proportions of circulating CD3+ T cells on day 3 (P = 0.0043), CD4+ (P = 0.0003) and CD8+ T cells (P = 0.005) on day 7, and CD11b+ monocytes on day 3 (P = 0.0046). After gonadectomy, these differences disappeared. In intact female mice, CD3+ T cells (P = 0.025), CD4+ T cells (P = 0.0178), CD8+ T cells (P = 0.0571), and CD68+ macrophages (P = 0.0078) increased in the fistula wall on days 3 and 7. This disappeared after gonadectomy. Furthermore, female mice had higher IL-10 (P = 0.0217) and TNF-α (P = 0.0417) levels in their AVF walls than male mice. Sex hormones mediate AVF maturation, suggesting that hormone receptor signaling may be a target to improve AVF maturation.NEW & NOTEWORTHY After arteriovenous fistula creation, females have lower rates of maturation and higher rates of failure than males. In a mouse model of venous adaptation that recapitulates human fistula maturation, sex hormones may be mechanisms of the sexual dimorphism: testosterone is associated with reduced shear stress, whereas estrogen is associated with increased immune cell recruitment. Modulating sex hormones or downstream effectors suggests sex-specific therapies and could address disparities in sex differences in clinical outcomes.

Sex Differences in the Anti-Hypertensive Effect of Calcium-Channel Blockers: A Systematic Review and Meta-Analysis

Cardiovascular disease (CVD) is the number one cause of death worldwide, with hypertension as the leading risk factor for both sexes. As sex may affect responsiveness to antihypertensive compounds, guidelines for CVD prevention might necessitate divergence between females and males. To this end, we studied the effectiveness of calcium channel blockers (CCB) on blood pressure (BP), heart rate (HR) and cardiac function between sexes. We performed a systematic review and meta-analysis on studies on CCB from inception to May 2020. Studies had to present both baseline and follow-up measurements of the outcome variables of interest and present data in a sex-stratified manner. Mean differences were calculated using a random-effects model. In total, 38 studies with 8202 participants were used for this review. In females as compared to males, systolic BP decreased by -27.6 mmHg (95%CI -36.4; -18.8) (-17.1% (95%CI -22.5;-11.6)) versus -14.4 mmHg (95%CI -19.0; -9.9) (-9.8% (95%CI -12.9;-6.7)) (between-sex difference p < 0.01), diastolic BP decreased by -14.1 (95%CI -18.8; -9.3) (-15.2%(95%CI -20.3;-10.1)) versus -10.6 mmHg (95%CI -14.0; -7.3) (-11.2% (95%CI -14.8;-7.7)) (between-sex difference p = 0.24). HR decreased by -1.8 bpm (95%CI -2.5; -1.2) (-2.5% (95%CI -3.4; -1.6)) in females compared to no change in males (0.3 bpm (95% CI -1.2; 1.8)) (between-sex difference p = 0.01). In conclusion, CCB lowers BP in both sexes, but the observed effect is larger in females as compared to males.

Cerebral blood flow and cerebrovascular resistance across the adult lifespan: A multimodality approach

Cerebral blood flow (CBF) decreases across the adult lifespan; however, more studies are needed to understand the underlying mechanisms. This study measured CBF and cerebrovascular resistance (CVR) using a multimodality approach in 185 healthy adults (21-80 years). Color-coded duplex ultrasonography and phase-contrast MRI were used to measure CBF, CBF velocity, and vessel diameters of the internal carotid (ICA) and vertebral arteries (VA). MRI arterial spin labeling was used to measure brain perfusion. Transcranial Doppler was used to measure CBF velocity at the middle cerebral artery. Structural MRI was used to measure brain volume. CBF was presented as total blood flow (mL/min) and normalized CBF (nCBF, mL/100g/min). Mean arterial pressure was measured to calculate CVR. Age was associated with decreased CBF by ∼3.5 mL/min/year and nCBF by ∼0.19 mL/100g/min/year across the methods. CVR increased by ∼0.011 mmHg/mL/100g/min/year. Blood flow velocities in ICA and VA decreased with age ranging from 0.07-0.15 cm/s/year, while the vessel diameters remained similar among age groups. These findings suggest that age-related decreases in CBF can be attributed mainly to decreases in blood flow velocity in the large cerebral arteries and that increased CVR likely reflects the presence of cerebral vasoconstrictions in the small cerebral arterioles and/or capillaries.

Abnormal physiological findings after FFR-based revascularisation deferral are associated with worse prognosis in women

The prognostic value of abnormal resting Pd/Pa and coronary flow reserve (CFR) after fractional flow reserve (FFR)-guided revascularisation deferral according to sex remains unknown. From the ILIAS Registry composed of 20 hospitals globally from 7 countries, patients with deferred lesions following FFR assessment (FFR > 0.8) were included. (NCT04485234) The primary clinical endpoint was target vessel failure (TVF) at 2-years follow-up. We included 1392 patients with 1759 vessels (n = 564 women, 31.9%). Although resting Pd/Pa was similar between the sexes (p = 0.116), women had lower CFR than men (2.5 [2.0-3.2] vs. 2.7 [2.1-3.5]; p = 0.004). During a 2-year follow-up period, TVF events occurred in 56 vessels (3.2%). The risk of 2-year TVF was significantly higher in women with low versus high resting Pd/Pa (HR: 9.79; p < 0.001), whereas this trend was not seen in men. (Sex: P-value for interaction = 0.022) Furthermore, resting Pd/Pa provided an incremental prognostic value for 2-year TVF over CFR assessment only in women. After FFR-based revascularisation deferral, low resting Pd/Pa is associated with higher risk of TVF in women, but not in men. The predictive value of Pd/Pa increases when stratified according to CFR values, with significantly high TVF rates in women in whom both indices are concordantly abnormal.Clinical Trial Registration: Inclusive Invasive Physiological Assessment in Angina Syndromes Registry (ILIAS Registry), NCT04485234.

Sexual and Reproductive Outcomes in Obese Fertile Men with Functional Hypogonadism after Treatment with Liraglutide: Preliminary Results

Purpose: To prospectively investigate the effects of treatment with liraglutide, a glucagon-like peptide 1 (GLP1) analog, on reproductive and sexual function in men with metabolic hypogonadism who are of childbearing age. Materials and Methods: To accomplish this purpose, 110 men of childbearing age (18-35 years) with metabolic hypogonadism were enrolled and divided into three groups, according to their desire to have children. Group A was made up of men actively seeking fatherhood, Group B, of men who did not seek fatherhood, and Group C, of men who had already fathered a child. Group A patients were treated with gonadotropins (urofollitropin at 150 IU, three times a week, and human chorionic gonadotropin at 2000 IU, twice a week), Group B patients with liraglutide (3 mg daily), and Group C patients with transdermal testosterone (60 mg per day). All patients were treated for 4 months. Results: Patients treated with liraglutide (Group B) showed significant improvement in conventional sperm parameters, compared to baseline and Group A patients, and in the quality of erectile function compared to baseline and patients of Groups A and C. In addition, they had significantly higher levels of total testosterone and sex hormone-binding globulin serum levels after 4 months of treatment with liraglutide than those achieved by patients in the other two groups at the end of the respective treatments. Finally, Group B patients also showed significantly higher serum gonadotropin levels than the other groups. Conclusions: The results of this study showed, for the first time, the efficacy of liraglutide, a GLP1 analog, for the pharmacological treatment of male patients with metabolic hypogonadism. Liraglutide has also shown advantages over traditional treatments on both reproductive and sexual function and appears to offer greater benefits in terms of metabolic protection. These findings suggest that liraglutide is a useful drug for the treatment of obese males with metabolic hypogonadism.

Young South Asian women in the United Kingdom show evidence of blunted endothelium-dependent dilatation: implications for future cardiovascular disease

INTRODUCTION

Prevalence of cardiovascular disease (CVD) is higher in South Asians than white Europeans. The offspring of hypertensive parents (OH) have greater risk of hypertension than offspring of normotensive parents (ON). We hypothesized that endothelium-dependent dilatation is already blunted in young South Asians, relative to young white European women, particularly in South Asian OH women.

METHODS

In young white European ON, South Asian ON and OH women (18-25 years old; 10 per group) who were normotensive, we recorded cutaneous perfusion by laser Doppler fluximetry during reactive hyperaemia and iontophoresis of acetylcholine (ACh), before and after inhibiting NO synthesis (NOS) or/and cyclooxygenase (COX). In these and an additional 135 age-matched South Asian and white European women, physical activity and life-style factors were assessed by questionnaire.

RESULTS

ACh-evoked dilatation was blunted in young South Asians, relative to white European women. It was attenuated by NOS or COX inhibition in white European ON; by NOS inhibition only in South Asian ON, but not OH women. After combined NOS and COX inhibition, ACh-evoked dilatations were similar to control ACh responses. Similar findings were made for reactive hyperaemia. Questionnaire data indicated young South Asians have lower physical activity levels, fresh fruit and vegetable intake than white European women, South Asian OH being lower than white European ON, or OH women.

CONCLUSION

Endothelium-dependent dilatation is blunted in young South Asians, relative to white European women, especially in South Asian OH in whom NO-dependent and prostaglandin-dependent dilatation is blunted. We suggest improved diet and greater physical activity could be particularly effective in improving endothelium-dependent dilatation and reducing future CVD risk in young South Asian OH women.

Additive damage in the thromboxane related vasoconstriction and bradykinin relaxation of intramural coronary resistance arterioles in a rodent model of andropausal hypertension

Hypertension and andropause both accelerate age–related vascular deterioration. We aimed to evaluate the effects of angiotensin-II induced hypertension and deficiency of testosterone combined regarding the resistance coronaries found intramurally.

Four male groups were formed from the animals: control group (Co, n = 10); the group that underwenr orchidectomy (ORC, n = 13), those that received an infusion of angiotensin-II (AII, n = 10) and a grous that received AII infusion and were also surgically orchidectomized (AII + ORC, n = 8). AII and AII + ORC animals were infused with infusing angiotensin-II (100 ng/min/kg) using osmotic minipumps. Orchidectomy was perfomed in the ORC and the AII + ORC groupsto establish deficiency regarding testosterone. Following four weeks of treatment, pressure-arteriography was performed in vitro, and the tone induced by administration of thromboxane-agonist (U46619) and bradykinin during analysis of the intramural coronaries (well-known to be resistance arterioles) was studied.

U46619-induced vasoconstriction poved to be significantly decreased in the ORC and AII + ORC groups when compared with Co and AII animals. In ORC and AII + ORC groups, the bradykinin-induced relaxation was also significantly reduced to a greater extent compared to Co and AII rats. Following orchidectomy, the vasocontraction and vasodilatation capacity of blood vessels is reduced. The effect of testosterone deficiency on constrictor tone and relaxation remains pronounced even in AII hypertension: testosterone deficiency further narrows adaptation range in the double noxa (AII + ORC) group. Our studies suggest that vascular changes caused by high blood pressure and testosterone deficiency together may significantly increase age-related cardiovascular risk.

Functions of Membrane Progesterone Receptors (mPRs, PAQRs) in Nonreproductive Tissues

Gender differences in a wide variety of physiological parameters have implicated the ovarian hormones, estrogens and progesterone, in the regulation of numerous nonreproductive tissue functions. Rapid, nongenomic (nonclassical) progesterone actions mediated by membrane progesterone receptors (mPRs), which belong to the progestin and adipoQ receptor family, have been extensively investigated in reproductive and nonreproductive tissues since their discovery in fish ovaries 20 years ago. The 5 mPR subtypes (α, β, γ, δ, ε) are widely distributed in vertebrate tissues and are often expressed in the same cells as the nuclear progesterone receptor (PR) and progesterone receptor membrane component 1, thereby complicating investigations of mPR-specific functions. Nevertheless, mPR-mediated progesterone actions have been identified in a wide range of reproductive and nonreproductive tissues and distinguished from nuclear PR-mediated ones by knockdown of these receptors with siRNA in combination with a pharmacological approach using mPR- and PR-specific agonists. There are several recent reviews on the roles of the mPRs in vertebrate reproduction and cancer, but there have been no comprehensive assessments of mPR functions in nonreproductive tissues. Therefore, this article briefly reviews mPR functions in a broad range of nonreproductive tissues. The evidence that mPRs mediate progesterone and progestogen effects on neuroprotection, lordosis behavior, respiratory control of apnea, olfactory responses to pheromones, peripheral nerve regeneration, regulation of prolactin secretion in prolactinoma, immune functions, and protective functions in vascular endothelial and smooth muscle cells is critically reviewed. The ubiquitous expression of mPRs in vertebrate tissues suggests mPRs regulate many additional nonreproductive functions that remain to be identified.

Incidence of infant mortality and its predictors in East Africa using Gompertz gamma shared frailty model

Background

Globally, infant mortality is a major public health concern and a sensitive indicator of countries' socio-economic and health status. Despite the substantial reduction of under-five mortality in sub-Saharan African countries specifically in East Africa, the infant mortality rate remains highest and too far below to achieve the WHO target. As to our search of the literature is concerned, there is a dearth of evidence on the incidence and predictors of infant mortality in East Africa. Therefore, this study investigated the incidence of infant mortality and its predictors in East Africa.

Methods

The present study has utilized 138,803 weighted samples from Demographic and Health Surveys (DHSs) of 12 East African countries. Considering the hierarchical nature of DHS data shared frailty parametric survival models were fitted and compared based on deviance (-2LLR), AIC, and BIC. Gompertz gamma shared frailty model was the best-fitted model for the data since it had the lowest deviance, AIC, and BIC values. Variables with a p-value < 0.2 in the bi-variable analysis were considered for the multivariable analysis. In the multivariable Gompertz gamma shared analysis, the Adjusted Hazard Ratio (AHR) with 95% Confidence Interval (CI) was reported to declare the significant predictors of infant mortality.

Results

The infant mortality rate in East Africa was 41.41 per 1000 live births. Mothers aged 25–34 years, wanted birth, health facility delivery, 1–3 ANC visit, being 2nd- 4th birth order, 5th and above, the birth interval of 24–48 months, and birth interval of 49 months and above were significantly associated with lower risk of infant mortality. Whereas women who didn’t have formal education, women who didn't participate in making health care decisions making, being male children, cesarean delivery, small size at birth, and large size at birth were significantly associated with a higher risk of infant mortality.

Conclusion

Despite the substantial progress in improving maternal and child health, this study showed that infant mortality is still a major public health concern in East Africa. Maternal age, place of delivery, maternal education, birth size, sex of the child, mode of delivery, women's autonomy, birth order, birth interval, and ANC visit were found to be significant predictors of infant mortality. Therefore, public health interventions enhancing health facility delivery, ANC visit, maternal education, birth spacing, and empowering women are crucial for reducing the incidence of infant mortality in East Africa.

Sex differences in hypertension. Do we need a sex-specific guideline?

Hypertension is the most prevalent cardiovascular disorder and the leading cause of death worldwide in both sexes. The prevalence of hypertension is lower in premenopausal women than in men of the same age, but sharply increases after the menopause, resulting in higher rates in women aged 65 and older. Awareness, treatment, and control of hypertension are better in women. A sex-pooled analysis from 4 community-based cohort studies found increasing cardiovascular risk beginning at lower systolic blood pressure thresholds for women than men. Hormonal changes after the menopause play a substantial role in the pathophysiology of hypertension in postmenopausal women. Female-specific causes of hypertension such as the use of contraceptive agents and assisted reproductive technologies have been identified. Hypertensive disorders in pregnancy are associated with increased risk of maternal, fetal, and neonatal morbidity and mortality, as well as with a greater risk of developing cardiovascular disease later in life. Hypertension-mediated organ damage was found to be more prevalent in women, thus increasing the cardiovascular risk. Sex differences in pharmacokinetics have been observed, but their clinical implications are still a matter of debate. There are currently no sufficient data to support sex-based differences in the efficacy of antihypertensive treatment. Adverse drug reactions are more frequently reported in women. Women are still underrepresented in large clinical trials in hypertension, and not all of them report sex-specific results. Therefore, it is of utmost importance to oblige scientists to include women in clinical trials and to consider sex as a biological variable.

Does wearing a mask while exercising amid COVID-19 pandemic affect hemodynamic and hematologic function among healthy individuals? Implications of mask modality, sex, and exercise intensity

OBJECTIVES

We investigated how wearing a mask - and its modality (surgical vs. N95) - affect hemodynamic and hematologic function in males and females across two exercise intensities (submaximal (SUB) and maximal (MAX)).

METHODS

144 individuals participated in the present study and were randomly allocated to three mask groups of 48 (N95, SURGICAL, and NO MASK) with two exercise subgroups for each mask group (MAX, n = 24; SUB, n = 24) for both sexes. Participants in each experimental group (N95SUB, N95MAX; SURSUB, SURMAX; SUB, MAX) were assessed for their hemodynamic and hematologic function at baseline and during recovery after exercise.

RESULTS

No significant differences were noted for either hemodynamic or hematologic function at post-exercise as compared to baseline with regard to mask modality (P > 0.05). Heart rate (HR) for maximal intensity were significantly greater at 1 min post-exercise in N95 as compared to SURGICAL (P < 0.05). No differences were noted for hemodynamic and hematologic function with N95 and SURGICAL compared to NOMASK for either intensity (P > 0.05). Females showed significantly greater HR values at 1 min post-exercise in N95 as compared to NO MASK, but no significant differences were noted for hematological function between sexes (P > 0.05).

CONCLUSION

Our findings show that wearing a face mask (N95/surgical) while exercising has no detrimental effects on hemodynamic/hematologic function in both males and females, and suggest that wearing a mask, particularly a surgical mask, while exercising during the ongoing pandemic is safe and poses no risk to individual's health. Future studies examining physiological responses to chronic exercise with masks are warranted.

Evaluation of the Interaction of Sex Hormones and Cardiovascular Function and Health

Purpose of Review

Sex hormones drive development and function of reproductive organs or the development of secondary sex characteristics but their effects on the cardiovascular system are poorly understood. In this review, we identify the gaps in our understanding of the interaction between sex hormones and the cardiovascular system.

Recent Findings

Studies are progressively elucidating molecular functions of sex hormones in specific cell types in parallel with the initiation of crucial large randomized controlled trials aimed at improving therapies for cardiovascular diseases (CVDs) associated with aberrant levels of sex hormones.

Summary

In contrast with historical assumptions, we now understand that men and women show different symptoms and progression of CVDs. Abnormal levels of sex hormones pose an independent risk for CVD, which is apparent in conditions like Klinefelter syndrome, androgen insensitivity syndrome, and menopause. Moreover, sex hormone–based therapies remain understudied and may not be beneficial for cardiovascular health.

Body Mass Index Mediates the Relationship between the Frequency of Eating Away from Home and Hypertension in Rural Adults: A Large-Scale Cross-Sectional Study

This study was conducted to investigate the association of eating away from home (EAFH) frequency with hypertension and to explore whether the association was mediated by BMI. A total of 29,611 participants were selected from the Henan Rural Cohort Study. Data on the frequency of EAFH were obtained by face-to-face questionnaires. The relationship between EAFH frequency and blood pressure was evaluated by linear regression. Logistic regression and restricted cubic spline were used to assess the association between EAFH frequency and hypertension, and the mediation effect of BMI on the relationship was performed. There were pronounced associations between the frequency of EAFH and blood pressure (P trend < 0.001) in the total population and men. Compared with the population with 0 times EAFH per week, the multivariate odds ratios (ORs) and 95% confidence intervals (95% CIs) for hypertension of the group with 7 times or more EAFH per week were 1.673 (1.482−1.889) for the total population and 1.634 (1.413−1.890) for men. A nonlinear dose-response relationship was detected between the frequency of EAFH and hypertension (p < 0.001), and the relationship was partially mediated by BMI. The proportion explained was 21.3% in the total population and 25.4% in men. The current study indicated that EAFH was associated with rising blood pressure and increased risk of hypertension and BMI partially mediated the relationship.

Blood Pressure and Stroke: A Review of Sex- and Ethnic/Racial-Specific Attributes to the Epidemiology, Pathophysiology, and Management of Raised Blood Pressure

Raised blood pressure (BP) is the leading cause of death and disability worldwide, and its particular strong association with stroke is well established. Although systolic BP increases with age in both sexes, raised BP is more prevalent in males in early adulthood, overtaken by females at middle age, consistently across all ethnicities/races. However, there are clear regional differences on when females overtake males. Higher BP among males is observed until the seventh decade of life in high-income countries, compared with almost 3 decades earlier in low- and middle-income countries. Females and males tend to have different cardiovascular disease risk profiles, and many lifestyles also influence BP and cardiovascular disease in a sex-specific manner. Although no hypertension guidelines distinguish between sexes in BP thresholds to define or treat hypertension, observational evidence suggests that in terms of stroke risk, females would benefit from lower BP thresholds to the magnitude of 10 to 20 mm Hg. More randomized evidence is needed to determine if females have greater cardiovascular benefits from lowering BP and whether optimal BP is lower in females. Since 1990, the number of people with hypertension worldwide has doubled, with most of the increase occurring in low- and-middle-income countries where the greatest population growth was also seen. Sub-Saharan Africa, Oceania, and South Asia have the lowest detection, treatment, and control rates. High BP has a more significant effect on the burden of stroke among Black and Asian individuals than Whites, possibly attributable to differences in lifestyle, socioeconomic status, and health system resources. Although pharmacological therapy is recommended differently in local guidelines, recommendations on lifestyle modification are often very similar (salt restriction, increased potassium intake, reducing weight and alcohol, smoking cessation). This overall enhanced understanding of the sex- and ethnic/racial-specific attributes to BP motivates further scientific discovery to develop more effective prevention and treatment strategies to prevent stroke in high-risk populations.

Genetic, Molecular, and Cellular Determinants of Sex-Specific Cardiovascular Traits

Despite the well-known sex dimorphism in cardiovascular disease traits, the exact genetic, molecular, and cellular underpinnings of these differences are not well understood. A growing body of evidence currently points at the links between cardiovascular disease traits and the genome, epigenome, transcriptome, and metabolome. However, the sex-specific differences in these links remain largely unstudied due to challenges in bioinformatic methods, inadequate statistical power, analytic costs, and paucity of valid experimental models. This review article provides an overview of the literature on sex differences in genetic architecture, heritability, epigenetic changes, transcriptomic signatures, and metabolomic profiles in relation to cardiovascular disease traits. We also review the literature on the associations between sex hormones and cardiovascular disease traits and discuss the potential mechanisms underlying these associations, focusing on human studies.

The regulation of PKA signaling in obesity and in the maintenance of metabolic health

The cAMP-dependent protein kinase (PKA) system represents a primary cell-signaling pathway throughout systems and across species. PKA facilitates the actions of hormones, neurotransmitters and other signaling molecules that bind G-protein coupled receptors (GPCR) to modulate cAMP levels. Through its control of synaptic events, exocytosis, transcriptional regulation, and more, PKA signaling regulates cellular metabolism and emotional and stress responses making it integral in the maintenance and dysregulation of energy homeostasis. Neural PKA signaling is regulated by afferent and peripheral efferent signals that link specific neural cell populations to the regulation of metabolic processes in adipose tissue, liver, pancreas, adrenal, skeletal muscle, and gut. Mouse models have provided invaluable information on the roles for PKA subunits in brain and key metabolic organs. While limited, human studies infer differential regulation of the PKA system in obese compared to lean individuals. Variants identified in PKA subunit genes cause Cushing syndrome that is characterized by metabolic dysregulation associated with endogenous glucocorticoid excess. Under healthy physiologic conditions, the PKA system is exquisitely regulated by stimuli that activate GPCRs to alter intracellular cAMP concentrations, and by PKA cellular localization and holoenzyme stability. Adenylate cyclase activity generates cAMP while phosphodiesterase-mediated cAMP degradation to AMP decreases cAMP levels downstream of GPCRs. Chronic perturbations in PKA signaling appear to be capable of resetting PKA regulation at several levels; in addition, sex differences in PKA signaling regulation, while not well understood, impact the physiologic consequences of metabolic dysregulation and obesity. This review explores the roles for PKA signaling in the pathogenesis of metabolic diseases including obesity, type 2 diabetes mellitus and associated co-morbidities through neural-peripheral crosstalk and cAMP/PKA signaling pathway targets that hold therapeutic potential.

Hormesis and Endothelial Progenitor Cells

Hormetic-biphasic dose response relationships are reported herein for human endothelial progenitor cells involving estradiol, nicotine, the anti-diabetic agent pioglitazone, resveratrol, and progesterone. In general, these studies demonstrate the capacity of these agents to enhance EPC proliferation and angiogenesis functional applications, having a focus on repairing endothelial tissue damage due to acute injury (e.g., stroke), as well as damage from chronic conditions (e.g., atherosclerosis) and normal aging processes.

Prevalence and determinants of hypertension in underrepresented indigenous populations of Nepal

Indigenous populations residing in low- and middle-income countries (LMICs) are highly underrepresented in medicine and public health research. Specifically, data on non-communicable diseases (NCDs) from indigenous populations remains scarce. Despite the increasing burden of NCDs in the Himalayan region, their prevalence in many indigenous populations remains understudied. The nationally representative public health surveys often do not include the indigenous communities, especially those that reside in rural areas or exist in small numbers. This observational cross-sectional survey study aimed to assess the prevalence of three NCD risk factors namely obesity, hypertension, and tachycardia and identify dietary and lifestyle variables associated with them across underrepresented indigenous populations of Nepal. A total of 311 individuals (53.3% women, 46.7% men) with mean age 43±15 years from 12 indigenous Nepali communities residing in rural (47.9%) or semi-urban (52.1%) areas volunteered to participate in this study. Univariate tests and multivariable logistic regressions were used to analyze the survey data. The mean systolic and diastolic blood pressures were 121.3±19.5 mmHg and 81.3±11.8 mmHg respectively. Overall, the prevalence of obesity and tachycardia was low (0.64% and 3.22%, respectively) but hypertension was prevalent at 23.8%. Hypertension was not significantly different across populations, but it was associated with age, BMI, and tobacco use, and collectively, these variables explained 13.9% variation in hypertension prevalence. Although we were unable to detect direct associations between individual determinants of hypertension identified in non-indigenous Nepalis, such as education levels, alcohol consumption, and smoking in this study, having one or more determinants increased the odds of hypertension in the indigenous participants. Furthermore, ~14% of the hypertensive individuals had none of the universally identified hypertension risk factors. The lack of association between previously identified risk factors for hypertension in these individuals indicates that the additional determinants of hypertension remain to be identified in indigenous Nepali populations.

Assessment of androgen receptor, IGF-IR and insulin receptor expression in male patients with severe peripheral artery disease

Background

Peripheral artery disease (PAD) of the lower limbs is a common condition that can affect quality of life. Androgen receptor (AR) can exert sex-specific effects on metabolic system, endothelial function and vascular tone. IGF-I receptor (IGF-IR) and insulin receptor (IR) may also be involved in the aforementioned functions. The aim of this study was to evaluate AR, IGF-IR and IR expression in the arterial vessel walls of PAD patients.

Results

This is a cross-sectional study examining 30 males with PAD undergoing open surgery procedures. Mean age was 75.9 ± 8.8y. All patients belonged to Rutherford stage 4–6. Median expression levels of IR, IGF-IR and AR significantly decreased from stage 4–6 (p < 0.05).

Significance

The study evidenced a progressive decrease of IR, IGF-IR and AR expression as the severity of disease increased. Altered levels of IR, IGF-IR and AR following PAD may be useful for the clinical evaluation of these patients.

Multi-Channel Bioimpedance System for Detecting Vascular Tone in Human Limbs: An Approach

Vascular tone plays a vital role in regulating blood pressure and coronary circulation, and it determines the peripheral vascular resistance. Vascular tone is dually regulated by the perivascular nerves and the cells in the inside lining of blood vessels (endothelial cells). Only a few methods for measuring vascular tone are available. Because of this, determining vascular tone in different arteries of the human body and monitoring tone changes is a vital challenge. This work presents an approach for determining vascular tone in human extremities based on multi-channel bioimpedance measurements. Detailed steps for processing the bioimpedance signals and extracting the main parameters from them have been presented. A graphical interface has been designed and implemented to display the vascular tone type in all channels with the phase of breathing during each cardiac cycle. This study is a key step towards understanding the way vascular tone changes in the extremities and how the nervous system regulates these changes. Future studies based on records of healthy and diseased people will contribute to increasing the possibility of early diagnosis of cardiovascular diseases.

Sexual dimorphism in cardiac remodeling: the molecular mechanisms ruled by sex hormones in the heart

Heart failure (HF) is growing in prevalence, due to an increase in aging and comorbidities. Heart failure with reduced ejection fraction (HFrEF) is more common in men, whereas heart failure with preserved ejection fraction (HFpEF) has a higher prevalence in women. However, the reasons for these epidemiological trends are not clear yet. Since HFpEF affects mostly postmenopausal women, sex hormones should play a pivotal role in HFpEF development. Furthermore, for HFpEF, contrary to HFrEF, effective therapeutic approaches are missing. Interestingly, studies evidenced that some therapies can have better results in women than in HFpEF men, emphasizing the necessity of understanding these observations at a molecular level. Thus, herein, we review the molecular mechanisms of estrogen and androgen actions in the heart in physiological conditions and explain how its dysregulation can lead to disease development. This clarification is essential in the road for an effective personalized management of HF, particularly HFpEF, towards the development of sex-specific therapeutic approaches.

Solving the Puzzle: What Is the Role of Progestogens in Neovascularization?

Ovarian sex steroids can modulate new vessel formation and development, and the clarification of the underlying mechanism will provide insight into neovascularization-related physiological changes and pathological conditions. Unlike estrogen, which mainly promotes neovascularization through activating classic post-receptor signaling pathways, progesterone (P4) regulates a variety of downstream factors with angiogenic or antiangiogenic effects, exerting various influences on neovascularization. Furthermore, diverse progestins, the synthetic progesterone receptor (PR) agonists structurally related to P4, have been used in numerous studies, which could contribute to unequal actions. As a result, there have been many conflicting observations in the past, making it difficult for researchers to define the exact role of progestogens (PR agonists including naturally occurring P4 and synthetic progestins). This review summarizes available evidence for progestogen-mediated neovascularization under physiological and pathological circumstances, and attempts to elaborate their functional characteristics and regulatory patterns from a comprehensive perspective.

Incidence and predictors of under-five mortality in East Africa using multilevel Weibull regression modeling

BACKGROUND

In 2017, an estimated 5.3 million under-five children died annually in Sub-Saharan African countries, more than half of those deaths occurred in East Africa. Though East African countries share the huge burden of global under-five mortality, there is limited evidence on the incidence and predictors of under-five mortality. Therefore, this study investigated the incidence and predictors of under-five mortality in East Africa.

METHODS

A community-based cross-sectional study was done based on the Demographic and Health Survey (DHS) data of 12 East African countries conducted from 2008 to 2019. A total weighted sample of 138,803 live births within 5 years preceding the survey were included for analysis. The Kaplan-Meier curve and Log-rank test were done to assess the children's survival experience across variable categories. The Global Schoenfeld residual test was employed for checking Proportional Hazard (PH) assumptions and it was violated (p-value< 0.05). Considering the hierarchical nature of DHS data, multilevel parametric survival models were fitted. Model comparison was made by AIC, deviance, and shape of the hazard function. Variables with a p-value of less than 0.2 in the bi-variable analysis were considered for the multivariable analysis. In the multilevel Weibull regression analysis, the Adjusted Hazard Ratio (AHR) with 95% Confidence Interval (CI) was reported to declare the significant predictors of under-five mortality.

RESULTS

Under-five mortality rate in East Africa was 51.318 (95% CI: 51.311, 51.323) per 1000 live births. Babies born to mothers attained secondary education and above (AHR = 0.83, 95% CI: 0.75, 0.91), being 2nd - 4th birth order (AHR = 0.62, 95% CI: 0.56, 0.67), ≥ 5th birth order (AHR = 0.68, 95% CI: 0.61, 0.76), health facility delivery (AHR = 0.87, 95% CI: 0.82, 0.93), 1-3 ANC visit (AHR = 0.61, 95% CI: 0.54, 0.68), births interval of 24-48 months (AHR = 0.53, 95% CI: 0.50, 0.57), wanted pregnancy (AHR = 0.72, 95% CI: 0.68, 0.76), middle wealth status (AHR = 0.90, 95% CI: 0.83, 0.97), and richest wealth status (AHR = 0.81, 95% CI:0.73, 0.90) were significantly associated with lower hazards of under-five mortality. Whereas, advanced maternal age (≥35 years) (AHR = 1.13, 95% CI: 1.04, 1.24),, babies born to household who did not have media exposure (AHR = 1.13, 95% CI: 1.07, 1.20), twin births (AHR = 3.81, 95% CI: 3.52, 4.12), being male child (AHR = 1.27, 95%CI: 1.21, 1.33), small birth size at birth (AHR = 1.73, 95% CI: 1.63, 1.84), and large size at birth (AHR = 1.11, 95% CI: 1.04, 1.11) were significantly associated with higher hazards of under-five mortality.

CONCLUSION

Under-five mortality is a major public health concern in East African countries. Health facility delivery, ANC visit, higher wealth status, adequate birth spacing, wanted pregnancy, and maternal education were significantly correlated with a lower risk of under-5 mortality. Whereas, higher birth order, small or large size at birth, male birth, twin birth, advanced maternal age and mothers who didn't have media exposure were significantly correlated with a higher risk of under-five mortality. This study highlights that public health programs should enhance health facility delivery, ANC visit, media exposure, maternal education, and adequate birth spacing to decrease the incidence of under-five mortality in East Africa.

Serum nitrite and nitrate: A potential biomarker for post-covid-19 complications?

Nitric oxide (NO) plays an important role in cardiovascular and immune systems. Quantification of blood nitrite and nitrate, two relatively stable metabolites of NO (generally as NO_x), has been acknowledged, in part, representing NO bioactivity. Dysregulation of NO_x had been reported in SARS-CoV-2 infected populations, but whether patients recovered from COVID-19 disease present with restored NO_x is unknown. In this study, serum NO₂^- and NO₃^- were quantified and analyzed among 109 recovered adults in comparison to a control group of 166 uninfected adults. Nitrite or nitrate levels were not significantly different among mild-, common-, severe- and critical-type patients. However, these recovered patients had dramatically lower NO₂^- and NO₂^-/NO₃^- than the uninfected group (p < 0.0001), with significantly higher NO₃^- levels (p = 0.0023) than the uninfected group. Nitrate and nitrite/nitrate were positively and negatively correlated with patient age, respectively, with age 65 being a turning point among recovered patients. These results indicate that low NO₂^-, low NO₂^-/NO₃^- and high NO₃^- may be potential biomarkers of long-term poor or irreversible outcomes after SARS-CoV-2 infection. It suggests that NO metabolites might serve as a predictor to track the health status of recovered COVID-19 patients, highlighting the need to elucidate the role of NO after SARS-CoV-2 infection.

Pregnancy as a Subgroup in the Pathophysiologic Classification of Spinal Aneurysms

BACKGROUND

Aneurysms of spinal arteries not associated with any known predisposing condition are referred to as isolated spinal aneurysms (SAs). In our series, an SA was found in 2 patients during the postpartum period. The goal of this study is to determine whether an occurrence of an SA may be related to puerperium.

METHODS

In a retrospective analysis of our consecutive series of 10 cases of SAs from 2008 to 2020, we identified 2 cases of SAs during puerperium. Patients' charts and imaging were reviewed, for potential predisposing factors.

RESULTS

In both cases, angiography showed fusiform aneurysms of the anterior SA with concomitant bilateral vertebral artery (VA) dissections. Serum vasculitis and inflammatory panel and genetic testing for collagen disorders were negative in both cases. Review of the literature showed that pregnancy is associated with an increased risk of arterial dissections in various locations and supports the hypothesis that hemodynamic and hormonal changes may play a role in the formation of SAs.

CONCLUSIONS

Pregnancy and peripartum state may be a distinct cause of the formation of SAs, possibly as a result of increased hemodynamic stress and hormonal changes that may alter the arterial wall. It would be appropriate to add pregnancy as a subgroup in the classification of SAs. In our series, both cases were associated with bilateral VA dissections; it is possible that the bilateral VA stenosis may have contributed to the formation of the SAs. It is important to recognize this possibility when considering the occlusion of a dissected VA.

Coronary Artery Disease in Women: A Comprehensive Appraisal

Coronary artery disease (CAD) is a significant cause of illness and death amongst women. The pathophysiology, manifestations, and outcomes of CVD and CAD differ between sexes. These sex differences remain under-recognized. The aim of this review is to highlight and raise awareness of the burden and unique aspects of CAD in women. It details the unique pathophysiology of CAD in women, cardiovascular risk factors in women (both traditional and sex-specific), the clinical presentation of CAD in women, and the range of disease in obstructive and non-obstructive CAD in women.