Arterial stiffness and hypertension

Impact of three-month treatment with pitavastatin on arterial stiffness in patients with hypercholesterolemia: a prospective observational study

OBJECTIVE

Although several studies have highlighted the benefits of statins in improving arterial stiffness, there is limited research on whether pitavastatin, a more recently developed statin, has similar effects. This study aimed to investigate the impact of pitavastatin on arterial stiffness in patients with hypercholesterolemia.

METHODS

This prospective study enrolled 115 patients with hypercholesterolemia (mean age, 59 years; 22% female) who had not previously been treated with statins. Participants underwent lifestyle interventions followed by administration of pitavastatin (2 or 4 mg daily) if target low-density lipoprotein (LDL) cholesterol levels were not achieved. The primary outcome measured was the change in brachial-ankle pulse wave velocity (baPWV) from baseline after three months of treatment.

RESULTS

Pitavastatin treatment significantly reduced LDL cholesterol by 41.1% (from 158 ± 28 to 93.0 ± 29.6 mg/dL; P < 0.001). Additionally, systolic blood pressure (SBP) decreased significantly from 130 ± 14 to 126 ± 14 mmHg (P < 0.001), representing a 2.9% reduction, and baPWV decreased significantly from 1522 ± 325 to 1407 ± 289 cm/s (P < 0.001), a 7.6% reduction. There was a significant correlation between changes in SBP and changes in baPWV (r = 0.565; P < 0.001). Even after adjusting for changes in SBP, the reduction in baPWV induced by pitavastatin remained statistically significant (P < 0.001).

CONCLUSION

A three-month treatment with pitavastatin effectively reduced arterial stiffness in patients with hypercholesterolemia, alongside significant improvements in lipid profiles and blood pressure reductions. These findings support the use of pitavastatin for managing key cardiovascular risk factors.

L-Arginine and Taurisolo® Effects on Brain Hypoperfusion-Reperfusion Damage in Hypertensive Rats

Acute and chronic hypertension causes cerebral vasculopathy, increasing the risk of ischemia and stroke. Our study aimed to compare the effects of arterial pressure reduction on the pial microvascular responses induced by hypoperfusion and reperfusion in spontaneously hypertensive Wistar rats, desamethasone-induced hypertensive Wistar rats and age-matched normotensive Wistar rats fed for 3 months with a normal diet or normal diet supplemented with L-arginine or Taurisolo® or L-arginine plus Taurisolo®. At the end of treatments, the rats were submitted to bilateral occlusion of common carotid arteries for 30 min and reperfusion. The microvascular parameters investigated in vivo through a cranial window were: arteriolar diameter changes, permeability increase, leukocyte adhesion to venular walls and percentage of capillaries perfused. Hypoperfusion-reperfusion caused in all rats marked microvascular changes. L-arginine treatment was effective in reducing arterial blood pressure causing vasodilation but did not significantly reduce the damage induced by hypoperfusion-reperfusion. Taurisolo® treatment was less effective in reducing blood pressure but prevented microvascular damage from hypoperfusion-reperfusion. L-arginine plus Taurisolo® maintained blood pressure levels within the physiological range and protected the pial microcirculation from hypoperfusion-reperfusion-induced microvascular injuries. Therefore, the blood pressure reduction is not the only fundamental aspect to protect the cerebral circulation from hypoperfusion-reperfusion damage.

Trends and Patterns in Hypertension-Related Deaths: A Comprehensive Analysis Using Center for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) Data

Hypertension (HTN) is a leading cause of cardiovascular morbidity and mortality worldwide. Despite advances in treatment, including the development and use of vasodilator-β-blocker combination and treatment with antihypertensive agents, HTN-related deaths have shown concerning trends. As such, the objective of this study is to examine the trends, disparities, and demographic variations in HTN-related mortality over a decade and to identify key factors contributing to these patterns, including genetics, dietary habits, structural discrimination in access to healthcare, lifestyle choices, and secondary hypertension, which is due to underlying conditions like kidney disease, hormonal disorders, or certain medications. To attain this objective, this retrospective study has utilized data from the Center for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) database to assess HTN-related mortality rates from 2010 to 2020. Age-adjusted mortality rates were calculated, and subgroup analyses were conducted by gender, race/ethnicity, and age groups. Temporal trends were analyzed to identify significant changes in mortality rates over time. Moreover, IBM SPSS Statistics, version 29 (IBM Corp., Armonk, NY) was used in the analysis, while 95% confidence intervals (CIs), were calculated to demonstrate the temporary trend of mortality rates overall and by age, sex, ethnicity, and region. Therefore, the mortality data from 2010 to 2020 show significant trends and variations across demographic groups. Overall, HTN-related mortality rate in the United States increased from 5.1 per 100,000 in 2010 to 6.4 in 2020, reflecting a general upward trend. For males, the rate rose from 4.8 to 6.6 per 100,000 during the same period. Racial disparities are notable, with Black or African American individuals having the highest mortality rates, increasing from 9.6 to 11.2 per 100,000. Age-specific data reveal that mortality in the 65-74 age group more than doubled, from 10.3 to 16.2 per 100,000, while in the 75-84 age group, it rose from 32.1 to 35.7. The 85+ age group had the highest rates, increasing from 144.0 to 155.0 per 100,000. States with the highest age-adjusted rates include Mississippi, Georgia, West Virginia, California, and Alabama. The study findings highlight the growing burden of HTN-related mortality in the United States, particularly among males, racial minorities, and older adults. This situation underscores the need for targeted public health interventions, which include creation of hypertension awareness in minority groups and enhancing medication adherence especially among Blacks, and addressing the social determinants of health contributing to higher HTN rates and poorer outcomes, including disadvantaged neighborhoods, structural discrimination and racism, and limited access to healthcare. The study found that African Americans are likely to be diagnosed with HTN earlier in life with higher HTN-related mortality than Whites, and with 50% increased risk of cardiovascular disease mortality. Continuous efforts are required to aptly address such disparities contributing to ongoing HTN treatment and care inequalities.

Is Arterial Stiffness Interconnected with Cardiovascular Drug Prescription Patterns, Body Composition Parameters, and the Quality of Blood Pressure Regulation in Hypertensive Patients?

BACKGROUND

Arterial hypertension (AH) is a significant risk factor for cardiovascular disease and is associated with increased arterial stiffness, particularly as measured by pulse wave velocity (PWV). This study aims to explore the relationships between age groups, antihypertensive and new oral antidiabetic drugs, body composition, and arterial stiffness parameters in hypertensive patients.

METHODS

A single-center cross-sectional study was conducted including 584 participants who underwent 24 h ambulatory blood pressure monitoring (including central blood pressure (BP) and PWV measurement), body composition analysis, and provided medical history and current pharmacotherapy data.

RESULTS

The study found that PWV was significantly higher in patients with poorly regulated BP in those aged 65 years and older. Significant PWV predictors included systolic BP, heart rate, peripheral mean arterial pressure, peripheral pulse pressure, augmentation index, calcium channel blockers, moxonidine, sodium-glucose co-transporter 2 inhibitors, urapidil, and statin prescription. Also, statistically significant negative correlations were found between PWV and visceral fat level, fat-free mass, and the percentage of muscle mass.

CONCLUSIONS

The findings suggest that arterial stiffness is interconnected with peripheral and central blood pressure parameters, body composition parameters, and prescribed hypertensive and new antidiabetic drugs.

Age-related annual changes in arterial stiffness in healthy adults: Insights from a large Korean cohort study

BACKGROUND AND AIMS

Arterial stiffness, a known cardiovascular risk factor, is associated with increasing age and arteriosclerosis. This study examines age-related annual changes in arterial stiffness in a large cohort of healthy individuals without cardiovascular disease, hypertension, or diabetes mellitus.

METHODS

The study included 195,405 Korean adults aged 30-79 years who attended a health check-up between 2006 and 2019. Arterial stiffness was assessed using brachial-ankle pulse wave velocity (baPWV), and the final cohort for the baPWV annual change analysis comprised 147,313 participants.

RESULTS

The study found that baPWV values increase progressively with age in both sexes, with the most notable changes occurring in the 70-79 age group. The spread in baPWV measurements, as indicated by the interquartile ranges, generally increases with age but was particularly pronounced in women in the 50s and 60s age groups, with men showing a greater spread in the 70-79 age group. The average annual change in baPWV (ΔbaPWV) values increased from 1.48 cm/s (95 % CI: 0.80-2.16) in the 30-39 age group to 23.72 cm/s (95 % CI: 16.25-31.19) in the 70-79 age group in men. Similarly, for women, the average ΔbaPWV values increased from 1.80 cm/s (95 % CI: 0.93-2.68) to 18.51 cm/s (95 % CI: 7.18-29.85) in the 30-39 and 70-79 age groups, respectively. The study observed that arterial stiffness in men consistently increases across all age groups, whereas in women, it does not significantly increase annually before age 50 but shows a steeper rise after this age.

CONCLUSIONS

This study emphasizes the progressive nature of arterial stiffness with aging in a healthy population. It highlights notable differences in the rate of progression and the distribution of baPWV between men and women, with men exhibiting a greater spread in the oldest age group.

Spontaneously Hypertensive Rats Present Exacerbated Focal Stroke Behavioral Outcomes

This study aimed to analyze the effects of systemic arterial hypertension (SAH) in a model of permanent ischemic stroke (focal ischemia due to thermocoagulation of pial vessels) on sensorimotor function (cylinder test and patch removal test), behavioral tasks (novelty habituation memory open field task) and cerebral infarct size in adult male spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto rats (WKY) for 42 days after the occurrence of a stroke. We observed that the stroke caused asymmetry in the front paws and delayed adhesive removal. These effects were spontaneously reduced in WKY rats, but not in SHR. Short- and long-term novelty habituation memories were abolished by stroke in WYK and SHR. On the 3rd day after stroke, the size of the focal cerebral infarct was the same in WKY and SHR. However, on the 7th day, the infarct size decreased in WKY rats, but not SHR. These results suggested that SAH impairment of sensorimotor recovery in rats subjected to cerebral ischemia could be related to augmented focal cerebral infarct size. Moreover, the behavioral tasks used in this study were unaffected by Systemic Arterial Hypertension. Our results highlight the need for animal models of comorbidities in stroke research.

Regulatory Roles of Long Non-Coding RNAs in Arterial Stiffness and Hypertension: Insights from Two African American Studies

Background

Arterial stiffness, commonly assessed via pulse wave velocity (PWV), is marked by reduced arterial elasticity and serves as a significant risk factor for cardiovascular disease and an early indicator of hypertension. This study investigated the regulatory roles of long non-coding RNAs (lncRNAs) in modulating mRNAs associated with arterial stiffness and hypertension, with a particular focus on African Americans, a population disproportionately impacted by hypertension.

Methods

We utilized whole-blood transcriptome sequencing data from two African American (AA) cohorts with high hypertension prevalence: the GENE-FORECAST study (436 subjects) and the MH-GRID study (179 subjects). Our objectives were to: (1) identify lncRNAs and mRNAs differentially expressed (DE) between the upper and lower tertiles of PWV, (2) determine DE lncRNAs associated with the expression levels of each DE mRNA, and (3) link the lncRNA-modulated mRNAs to hypertension across both datasets.

Results

Differential expression analysis revealed 1,035 DE mRNAs and 31 DE lncRNAs between upper and lower PWV groups. Then lncRNA-mRNA pairs significantly associated were identified, involving 31 unique lncRNAs and 1,034 unique mRNAs. Finally, 22 of the lncRNA-modulated mRNAs initially linked to PWV were found associated with hypertension, in both datasets. Interestingly, 30 lncRNAs were linked to the expression of UCP2 (Uncoupling Protein 2), a gene implicated in oxidative stress and endothelial function.

Conclusions

Our findings underscore the significant roles of lncRNAs in regulating gene expression associated with arterial stiffness and hypertension. The differential expression of UCP2 in relation to PWV and hypertension, along with its potential regulation by lncRNAs, offers valuable insights into the molecular mechanisms underlying arterial stiffness and its connection with hypertension.

Association between oxidative balance score and resistant hypertension and arterial stiffness among US adults: A population-based study

BACKGROUND AND AIMS

Prior studies have established the correlation between oxidative balance score (OBS) and hypertension (HTN). While the association between OBS and resistant hypertension (RHT) as well as arterial stiffness among individuals with hypertension remains undisclosed.

METHODS AND RESULTS

In this study, total of 15,910 adults diagnosed with hypertension were enrolled from NHANES 2001-2018. OBS was calculated and categorized into quartiles. Weighted regression model, stratified analyses and restricted cubic spline (RCS) were employed to evaluate the association between OBS and RHT, major adverse cardiovascular events (MACEs) and arterial stiffness in individuals with hypertension. Among enrolled participants, high OBS quartiles consistently demonstrated a negative association with resistant hypertension across all models (all p < 0.05), indicating robust stability. Compared with the lowest OBS quartile, the risk of resistant hypertension in the highest OBS quartile was decreased by 30.8% (95%CI 0.471-0.995, p = 0.049). After dividing OBS into dietary OBS and lifestyle OBS, a significant inverse association with lifestyle OBS and RHT was observed. With regard to MACEs, the inverse association was also found in participants with high OBS. Besides, the potential relation between OBS and arterial stiffness was explored and we found OBS was significantly associated with decreased arterial stiffness (β for ePWV, -0.014; 95%CI -0.026 to -0.001; p = 0.032). RCS analysis confirmed a nonlinear association between OBS and RHT, MACEs, cardiovascular death and nonfatal MI among participants with hypertension.

CONCLUSION

Elevated OBS was negatively associated with the risk of RHT and arterial stiffness among US adults with hypertension.

Do Photopletysmographic Parameters of Arterial Stiffness Differ Depending on the Presence of Arterial Hypertension and/or Atherosclerosis?

BACKGROUND

Hypertension and atherosclerotic cardiovascular diseases (ASCVD) increase cardiovascular risk and worsen patients' prognoses. One early predictor of increased risk is a change in arterial stiffness. This study aimed to evaluate arterial stiffness parameters using the non-invasive photoplethysmography (PPG) method in Polish patients with arterial hypertension (AH) and/or atherosclerosis (AS).

METHODS

The study group consisted of 333 patients (Caucasians, both sexes, aged 30-85 years old). Patients were analyzed in four groups depending on AH and AS (Group I: patients without AH or AS, Group II: AH patients, Group III: AS patients, and Group IV: AH/AS patients) and, in addition, according to sex and history of SARS-CoV-2 infection. Arterial stiffness parameters, i.e., reflection index (RI), peak-to-peak time (PPT), and stiffness index (SI) were automatically calculated with PPG based on the analysis of the pulse wave contour.

RESULTS

Mean values of RI and SI were higher in men than women (p < 0.001 each). Diastolic blood pressure (DBP) also differed between sexes (p = 0.010). Mean SI values differed between the study groups (p = 0.038) with the highest SI found in AS/AH patients and the lowest-in patients without AH or AS. The mean SI values were significantly lower in women compared to men in both Group I and Group II (p = 0.006 and p < 0.001, respectively). The mean values of RI were also greater in men than in women in Group I and Group II (p < 0.001 for each group). Regarding COVID-19 history, only HR values differed between patients with and without COVID-19 in AH patients (p = 0.012). In AH patients, men had higher values of RI and SI compared to women (p < 0.001 and p < 0.001). On the other hand, AS women with COVID-19 had significantly greater mean values of SI (9.66 m/s ± 1.61) than men with COVID-19 (7.98 m/s ± 1.09) (p = 0.045).

CONCLUSIONS

The present study confirmed that sex had a significant impact on arterial stiffness parameters. Both AH and AS affected arterial stiffness. Heart rate was greater in hypertensive patients after COVID-19 compared to hypertensive patients without COVID-19.

Genome-Wide Characterization of Somatic Mutation Patterns in Cloned Dogs Reveals Implications for Neuronal Function, Tumorigenesis, and Aging

Studies on somatic mutations in cloned animals have revealed slight genetic variances between clones and their originals, but have yet to identify the precise effects of these differences within the organism. Somatic mutations contribute to aging and are implicated in tumor development and other age-related diseases. Thus, we compared whole genome sequencing data from an original dog with that of cloned dogs, identifying candidate somatic mutations that were disproportionately located within genes previously implicated in aging. The substitutional signature of cloning-specific somatic mutations mirrored the uniform distribution characteristic of the signature associated with human aging. Further analysis of genes revealed significant enrichment of traits associated with body size as well as the molecular mechanisms underlying neuronal function and tumorigenesis. Overall, the somatic mutations found in cloned dogs may indicate a conserved mechanism driving aging across species and a broad spectrum of pathway alterations.

Arterial Stiffness and Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is prevalent and associated with a poor prognosis, imposing a significant burden on society. Arterial stiffness is increasingly recognized as a crucial factor in the pathophysiology of HFpEF, affecting diagnosis, management, and prognosis. As a hallmark of vascular aging, arterial stiffness contributes to increased afterload on the left ventricle (LV), leading to diastolic dysfunction, a key feature of HFpEF. Elevated arterial stiffness is linked with common cardiovascular risk factors in HFpEF, such as hypertension, diabetes and obesity, exacerbating the progression of disease. Studies have demonstrated that patients with HFpEF exhibit significantly higher levels of arterial stiffness compared to those without HFpEF, highlighting the value of arterial stiffness measurements as both diagnostic and prognostic tools. Moreover, interventions aimed at reducing arterial stiffness, whether through pharmacological therapies or lifestyle modifications, have shown potential in improving LV diastolic function and patient outcomes. Despite these advancements, the precise mechanisms by which arterial stiffness contributes to HFpEF are still not fully understood, necessitating the need for further research.

Early vascular aging in acute ischemic stroke: A systematic review and meta-analysis

BACKGROUND

While arterial stiffening is a known risk factor for cardiovascular diseases, it remains unclear whether there is an early vascular aging (EVA) in patients who have experienced acute ischemic stroke (AIS). This systematic review and meta-analysis aims to investigate whether patients with AIS exhibit EVA through pulse wave velocity (PWV) measurements shortly after the stroke onset, shedding light on the relationship between arterial stiffness, hypertension, and stroke.

METHODS

Thirteen case-control studies were included, comparing PWV measurements between AIS patients and non-AIS individuals. A meta-analysis was performed to compare PWV levels, age, blood pressure, and the prevalence of different cardiovascular risk factors among 1711 AIS patients and 1551 controls.

RESULTS

Despite AIS patients showing higher PWV compared to controls (mean difference: 1.72 m/s, 95 % CI: 1.05-2.38, p < 0.001; I2 = 88.3 %), their age did not significantly differ (95 % CI: -0.47-0.94, p = 0.519; I2 = 0 %), suggesting EVA in AIS patients. Moreover, AIS patients exhibited elevated systolic and diastolic blood pressure and had higher odds of smoking, hypertension, diabetes, and male gender compared to controls.

CONCLUSIONS

This study's findings underscore the presence of EVA in AIS patients, evident through increased PWV measurements shortly after stroke onset. Notably, smoking, hypertension, and diabetes mellitus emerge as substantial factors contributing to accelerated arterial stiffness within this population.

Effects of 12-week Circuit Exercise Intervention on Blood Pressure, Vascular Function, and Inflammatory Cytokines in Obese Older Women with Sarcopenia

Background

This study investigates the effects of a 12-week circuit exercise program on blood pressure, vascular function, and inflammatory cytokines in older obese women with sarcopenia.

Methods

Twenty-eight older obese women with sarcopenia (mean age: 78.2 ± 3.7 years) were randomly divided into an exercise group (EG, n = 14) and a control group (CG, n = 14). The EG participated in a 12-week circuit exercise training regimen, conducted three times weekly, with each session lasting between 45 to 75 minutes (progressively increased over time). The CG was advised to maintain their regular daily routines throughout the intervention period. All dependent variables, including blood pressure, vascular function, and inflammation cytokines, were evaluated pre- and post-intervention.

Results

Positive changes were observed in the EG in body composition (body fat mass; p < 0.001, body fat percentage; p < 0.01, free-fat mass; p < 0.01), blood pressure (heart rate; p < 0.05, rate pressure product; p < 0.01), vascular function (brachial-ankle pulse wave velocity; p < 0.05, flow-mediated dilation; p < 0.001), and inflammation cytokines (interleukin-6; p < 0.05). In the CG, there was an increase in body fat mass (p < 0.05) and body fat percentage (p < 0.05), while no changes were observed in other variables.

Conclusions

The 12-week circuit exercise program significantly reduced blood pressure, improved vascular function, and decreased inflammatory cytokines in obese older women with sarcopenia. However, individual variations in response highlight the need for personalized exercise regimens.

Synergistic Effects of Weight Loss and Catheter Ablation: Can microRNAs Serve as Predictive Biomarkers for the Prevention of Atrial Fibrillation Recurrence?

In atrial fibrillation (AF), multifactorial pathologic atrial alterations are manifested by structural and electrophysiological changes known as atrial remodeling. AF frequently develops in the context of underlying cardiac abnormalities. A critical mechanistic role played by atrial stretch is played by abnormal substrates in a number of conditions that predispose to AF, including obesity, heart failure, hypertension, and sleep apnea. The significant role of overweight and obesity in the development of AF is known; however, the differential effect of overweight, obesity, cardiovascular comorbidities, lifestyle, and other modifiable risk factors on the occurrence and recurrence of AF remains to be determined. Reverse remodeling of the atrial substrate and subsequent reduction in the AF burden by conversion into a typical sinus rhythm has been associated with weight loss through lifestyle changes or surgery. This makes it an essential pillar in the management of AF in obese patients. According to recently published research, microRNAs (miRs) may function as post-transcriptional regulators of genes involved in atrial remodeling, potentially contributing to the pathophysiology of AF. The focus of this review is on their modulation by both weight loss and catheter ablation interventions to counteract atrial remodeling in AF. Our analysis outlines the experimental and clinical evidence supporting the synergistic effects of weight loss and catheter ablation (CA) in reversing atrial electrical and structural remodeling in AF onset and in recurrent post-ablation AF by attenuating pro-thrombotic, pro-inflammatory, pro-fibrotic, arrhythmogenic, and male-sex-associated hypertrophic remodeling pathways. Furthermore, we discuss the promising role of miRs with prognostic potential as predictive biomarkers in guiding approaches to AF recurrence prevention.

Cardiovascular Consequences of Uremic Metabolites: an Overview of the Involved Signaling Pathways

The crosstalk of the heart with distant organs such as the lung, liver, gut, and kidney has been intensively approached lately. The kidney is involved in (1) the production of systemic relevant products, such as renin, as part of the most essential vasoregulatory system of the human body, and (2) in the clearance of metabolites with systemic and organ effects. Metabolic residue accumulation during kidney dysfunction is known to determine cardiovascular pathologies such as endothelial activation/dysfunction, atherosclerosis, cardiomyocyte apoptosis, cardiac fibrosis, and vascular and valvular calcification, leading to hypertension, arrhythmias, myocardial infarction, and cardiomyopathies. However, this review offers an overview of the uremic metabolites and details their signaling pathways involved in cardiorenal syndrome and the development of heart failure. A holistic view of the metabolites, but more importantly, an exhaustive crosstalk of their known signaling pathways, is important for depicting new therapeutic strategies in the cardiovascular field.

The potential effect of natural antioxidants on endothelial dysfunction associated with arterial hypertension

Arterial hypertension represents a leading cause of cardiovascular morbidity and mortality worldwide, and the identification of effective solutions for treating the early stages of elevated blood pressure (BP) is still a relevant issue for cardiovascular risk prevention. The pathophysiological basis for the occurrence of elevated BP and the onset of arterial hypertension have been widely studied in recent years. In addition, consistent progress in the development of novel, powerful, antihypertensive drugs and their appropriate applications in controlling BP have increased our potential for successfully managing disease states characterized by abnormal blood pressure. However, the mechanisms responsible for the disruption of endogenous mechanisms contributing to the maintenance of BP within a normal range are yet to be fully clarified. Recently, evidence has shown that several natural antioxidants containing active ingredients originating from natural plant extracts, used alone or in combination, may represent a valid solution for counteracting the development of arterial hypertension. In particular, there is evidence to show that natural antioxidants may enhance the viability of endothelial cells undergoing oxidative damage, an effect that could play a crucial role in the pathophysiological events accompanying the early stages of arterial hypertension. The present review aims to reassess the role of oxidative stress on endothelial dysfunction in the onset and progression of arterial hypertension and that of natural antioxidants in covering several unmet needs in the treatment of such diseases.

Possible Molecular Mechanisms of Hypertension Induced by Sleep Apnea Syndrome/Intermittent Hypoxia

Intermittent hypoxia (IH) is a central characteristic of sleep apnea syndrome (SAS), and it subjects cells in the body to repetitive apnea, chronic hypoxia, oxygen desaturation, and hypercapnia. Since SAS is linked to various serious cardiovascular complications, especially hypertension, many studies have been conducted to elucidate the mechanism of hypertension induced by SAS/IH. Hypertension in SAS is associated with numerous cardiovascular disorders. As hypertension is the most common complication of SAS, cell and animal models to study SAS/IH have developed and provided lots of hints for elucidating the molecular mechanisms of hypertension induced by IH. However, the detailed mechanisms are obscure and under investigation. This review outlines the molecular mechanisms of hypertension in IH, which include the regulation systems of reactive oxygen species (ROS) that activate the renin-angiotensin system (RAS) and catecholamine biosynthesis in the sympathetic nervous system, resulting in hypertension. And hypoxia-inducible factors (HIFs), Endotheline 1 (ET-1), and inflammatory factors are also mentioned. In addition, we will discuss the influences of SAS/IH in cardiovascular dysfunction and the relationship of microRNA (miRNA)s to regulate the key molecules in each mechanism, which has become more apparent in recent years. These findings provide insight into the pathogenesis of SAS and help in the development of future treatments.