Vascular Ageing and Exercise: Focus on Cellular Reparative Processes

Effects of regular aerobic exercise on vascular function in overweight or obese older adults: A systematic review and meta-analysis

Background

Overweight and obese older adults have a high risk for developing cardiovascular disease. Aerobic exercise is a valuable strategy to improve vascular health, but the effects of aerobic exercise on vascular endothelial function in obese and overweight older adults remain controversial. The purpose of this meta-analysis was to investigate the effects of aerobic exercise on vascular function in obese and overweight older adults with or without comorbidity.

Methods

A systematic literature search for related studies published in English was conducted between January 1989 and October 30, 2022, in the PubMed, Embase, and Cochrane Library databases. A random effects model was chosen for meta-analysis, which calculated the effect sizes of control and intervention groups after exercise intervention using standardized mean differences (SMDs) corrected for Hedges' g bias and 95% confidence intervals (95% CIs).

Results

Twenty-six studies containing 1418 participants were included in the study. After excluding three studies contributing to higher heterogeneity by sensitivity analysis, there are small effects of regular aerobic exercise on vascular function of obese and overweight older adults, including flow-mediated dilation (FMD) [SMD = 0.21, 95% CI (0.02, 0.41), z = 2.16, df = 19, I² = 52.2%, P = 0.031] and pulse wave velocity (PWV) [SMD = -0.24, 95% CI (-0.46, -0.02), z = 2.17, df = 10, I² = 8.6%, P = 0.030], and no significant effect was observed on augmentation index (Aix). Subgroup analysis showed small effects of regular aerobic exercise on FMD [SMD = 0.37, 95% CI (0.13, 0.61), z = 3.05, df = 9, I² = 52.6%, P = 0.002] in the overweight not obese subgroup (25 = BMI <30 kg/m²), but no significant effect on the obese subgroup (BMI ≥30 kg/m²). Regular aerobic exercise for more than 24 weeks improved FMD by small effect sizes [SMD = 0.48, 95% CI (0.04, 0.93), z = 2.12, df = 5, I² = 56.4%, P = 0.034] and for more than three times per week improved FMD by moderate effect sizes [SMD = 0.55, 95% CI (0.12, 0.98), z = 2.50, df = 3, I² = 31.1%, P = 0.012] in obese and overweight older adults with or without CVD.

Conclusion

In obese and overweight older adults with or without comorbidity, regular aerobic exercise for more than 24 weeks improved FMD by small effect sizes and exercise for more than three times per week improved FMD by moderate effect sizes and regular aerobic exercise reduced PWV by small effect sizes and had no influence on Aix. Taken together, it was recommended that obese and overweight older adults should adhere to regular aerobic exercise, training at least 3 times per week for better results.

Use of the Vascular Overload Index to Predict Cardiovascular Disease in a Rural Population of China

Objective

To explore the relationship between vascular overload index (VOI) and cardiovascular disease (CVD) in rural population and find effective ways to prevent cardiovascular disease in rural low-income populations.

Methods

The data for this study was obtained from a large cohort study called the Northeast China Rural Cardiovascular Health Study (NCRCHS) conducted in 2013 and followed up during 2015-2018. 10,174 subjects completed at least one follow-up visit. Cox regression equation was used to explore whether VOI and cardiovascular disease were independently related. The Kaplan-Meier curves were used to calculate the cumulative incidence of any adverse outcome, and the log-rank test and restrict mean survival analysis were used to compare group differences. Reclassification and discrimination statistics were used to determine whether VOI could strengthen the ability of the model to predict CVD events.

Results

The prevalence of CVD in the VOI quartiles was 1.92%, 3.96%, 5.42%, and 11.34% for Q1-Q4, respectively (P for trend <0.001). After adjusting for multiple confounders, there was a 2.466-fold increased risk of CVD when comparing the highest and lowest groups. Besides, this study found that for every standard deviation increase, the results still exist. The risk of cardiovascular disease increased by 1.358-fold in this model. The restrict mean survival analysis results show that with the increase of VOI, the restrict mean survival time (RMST) within 5 years gradually became shorter. Reclassification and discrimination statistics indicated that VOI significantly enhanced the ability to estimate CVD events within 4 years.

Conclusion

Analyses showed that VOI was significantly associated with CVD. VOI is a simple and accurate prognostic marker of CVD risk, which has the potential ability to improve the risk stratification of CVD.

Clinical assessment of endothelial function in convalescent COVID-19 patients: a meta-analysis with meta-regressions

BACKGROUND

Endothelial dysfunction has been proposed to play a key role in the pathogenesis of coronavirus disease 2019 (COVID-19) and its post-acute sequelae. Flow-mediated dilation (FMD) is recognized as an accurate clinical method to assess endothelial function. Thus, we performed a meta-analysis of the studies evaluating FMD in convalescent COVID-19 patients and controls with no history of COVID-19.

METHODS

A systematic literature search was conducted in the main scientific databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Using the random effects method, differences between cases and controls were expressed as mean difference (MD) with 95% confidence intervals (95% CI). The protocol was registered on PROSPERO with reference number CRD42021289684.

RESULTS

Twelve studies were included in the final analysis. A total of 644 convalescent COVID-19 patients showed significantly lower FMD values as compared to 662 controls (MD: -2.31%; 95% CI: -3.19, -1.44; p < 0.0001). Similar results were obtained in the sensitivity analysis of the studies that involved participants in either group with no cardiovascular risk factors or history of coronary artery disease (MD: -1.73%; 95% CI: -3.04, -0.41; p = 0.010). Interestingly, when considering studies separately based on enrolment within or after 3 months of symptom onset, results were further confirmed in both short- (MD: -2.20%; 95% CI: -3.35, -1.05; p < 0.0001) and long-term follow-up (MD: -2.53%; 95% CI: -4.19, -0.86; p = 0.003). Meta-regression models showed that an increasing prevalence of post-acute sequelae of COVID-19 was linked to a higher difference in FMD between cases and controls (Z-score: -2.09; p = 0.037).

CONCLUSIONS

Impaired endothelial function can be documented in convalescent COVID-19 patients, especially when residual clinical manifestations persist. Targeting endothelial dysfunction through pharmacological and rehabilitation strategies may represent an attractive therapeutic option.Key messagesThe mechanisms underlying the post-acute sequelae of coronavirus disease 2019 (COVID-19) have not been fully elucidated.Impaired endothelial function can be documented in convalescent COVID-19 patients for up to 1 year after infection, especially when residual clinical manifestations persist.Targeting endothelial dysfunction may represent an attractive therapeutic option in the post-acute phase of COVID-19.

Effect of Exercise on Vascular Function and Blood Lipids in Postmenopausal Women: A Systematic Review and Network Meta-Analysis

This study aimed to compare and rank the effectiveness of aerobic exercise (AE), resistance training (RT), combined training (CT), and water exercise (WE) on vascular function and blood lipids in postmenopausal women using a network meta-analysis (NMA).

METHODS

We searched the PubMed, Cochrane, Embase, Web of Science, and EBSCO (SPORTDiscus) databases to identify randomized controlled trials investigating the effects of exercise on vascular function and blood lipids in postmenopausal women. The retrieval period was from inception to March 2022. Two reviewers independently screened the retrieved articles, extracted pertinent data, and assessed the risk of bias of the included studies.

RESULTS

A total of 38 studies involving 1407 patients were included in this study. The results of the NMA indicated that WE had the greatest effect on systolic blood pressure (SBP) (surface under the cumulative ranking [SUCRA] = 84.9) and total cholesterol (TC) (SUCRA = 93.1); CT had the greatest effect on triglycerides (TG) (SUCRA = 96.2), high-density lipoprotein cholesterol (HDL-C) (SUCRA = 94.8), and diastolic blood pressure (DBP) (SUCRA = 91.1); RT had the greatest effect on low-density lipoprotein cholesterol (LDL-C) (SUCRA = 79.4).

CONCLUSION

The results suggest that exercise can effectively improve the PWV, SBP, and DBP and the levels of TC, TG, and LDL-C in postmenopausal women. WE had the best effect on improving TC and SBP. CT had the best effect on improving TG, HDL-C, and DBP. To improve LDL-C, RT can achieve a good effect. Considering the limitations of NMA, more RCTS need to be performed in the future to provide more direct evidence of the effectiveness of various exercise interventions on vascular health in postmenopausal women.

Impact of Non-Pharmacological Interventions on the Mechanisms of Atherosclerosis

Atherosclerosis remains the leading cause of mortality and morbidity worldwide characterized by the deposition of lipids and fibrous elements in the form of atheroma plaques in vascular areas which are hemodynamically overloaded. The global burden of atherosclerotic cardiovascular disease is steadily increasing and is considered the largest known non-infectious pandemic. The management of atherosclerotic cardiovascular disease is increasing the cost of health care worldwide, which is a concern for researchers and physicians and has caused them to strive to find effective long-term strategies to improve the efficiency of treatments by managing conventional risk factors. Primary prevention of atherosclerotic cardiovascular disease is the preferred method to reduce cardiovascular risk. Fasting, a Mediterranean diet, and caloric restriction can be considered useful clinical tools. The protective impact of physical exercise over the cardiovascular system has been studied in recent years with the intention of explaining the mechanisms involved; the increase in heat shock proteins, antioxidant enzymes and regulators of cardiac myocyte proliferation concentration seem to be the molecular and biochemical shifts that are involved. Developing new therapeutic strategies such as vagus nerve stimulation, either to prevent or slow the disease’s onset and progression, will surely have a profound effect on the lives of millions of people.

Current Understanding of Molecular Pathophysiology of Heart Failure With Preserved Ejection Fraction

Heart Failure (HF) is the most common cause of hospitalization in the Western societies. HF is a heterogeneous and complex syndrome that may result from any dysfunction of systolic or diastolic capacity. Abnormal diastolic left ventricular function with impaired relaxation and increased diastolic stiffness is characteristic of heart failure with preserved ejection fraction (HFpEF). HFpEF accounts for more than 50% of all cases of HF. The prevalence increases with age: from around 1% for those aged &lt;55 years to &gt;10% in those aged 70 years or over. Nearly 50% of HF patients have HFrEF and the other 50% have HFpEF/HFmrEF, mainly based on studies in hospitalized patients. The ESC Long-Term Registry, in the outpatient setting, reports that 60% have HFrEF, 24% have HFmrEF, and 16% have HFpEF. To some extent, more than 50% of HF patients are female. HFpEF is closely associated with co-morbidities, age, and gender. Epidemiological evidence suggests that HFpEF is highly represented in older obese women and proposed as ‘obese female HFpEF phenotype’. While HFrEF phenotype is more a male phenotype. In addition, metabolic abnormalities and hemodynamic perturbations in obese HFpEF patients appear to have a greater impact in women then in men (Sorimachi et al., European J of Heart Fail, 2022, 22). To date, numerous clinical trials of HFpEF treatments have produced disappointing results. This outcome suggests that a “one size fits all” approach to HFpEF may be inappropriate and supports the use of tailored, personalized therapeutic strategies with specific treatments for distinct HFpEF phenotypes. The most important mediators of diastolic stiffness are the cardiomyocytes, endothelial cells, and extracellular matrix (ECM). The complex physiological signal transduction networks that respond to the dual challenges of inflammatory and oxidative stress are major factors that promote the development of HFpEF pathologies. These signalling networks contribute to the development of the diseases. Inhibition and/or attenuation of these signalling networks also delays the onset of disease. In this review, we discuss the molecular mechanisms associated with the physiological responses to inflammation and oxidative stress and emphasize the nature of the contribution of most important cells to the development of HFpEF via increased inflammation and oxidative stress.

Mechanisms and Clinical Implications of Endothelial Dysfunction in Arterial Hypertension

The endothelium is composed of a monolayer of endothelial cells, lining the interior surface of blood and lymphatic vessels. Endothelial cells display important homeostatic functions, since they are able to respond to humoral and hemodynamic stimuli. Thus, endothelial dysfunction has been proposed as a key and early pathogenic mechanism in many clinical conditions. Given the relevant repercussions on cardiovascular risk, the complex interplay between endothelial dysfunction and systemic arterial hypertension has been a matter of study in recent years. Numerous articles have been published on this issue, all of which contribute to providing an interesting insight into the molecular mechanisms of endothelial dysfunction in arterial hypertension and its role as a biomarker of inflammation, oxidative stress, and vascular disease. The prognostic and therapeutic implications of endothelial dysfunction have also been analyzed in this clinical setting, with interesting new findings and potential applications in clinical practice and future research. The aim of this review is to summarize the pathophysiology of the relationship between endothelial dysfunction and systemic arterial hypertension, with a focus on the personalized pharmacological and rehabilitation strategies targeting endothelial dysfunction while treating hypertension and cardiovascular comorbidities.

Endothelial Dysfunction in COVID-19: A Unifying Mechanism and a Potential Therapeutic Target

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) generated a worldwide emergency, until the declaration of the pandemic in March 2020. SARS-CoV-2 could be responsible for coronavirus disease 2019 (COVID-19), which goes from a flu-like illness to a potentially fatal condition that needs intensive care. Furthermore, the persistence of functional disability and long-term cardiovascular sequelae in COVID-19 survivors suggests that convalescent patients may suffer from post-acute COVID-19 syndrome, requiring long-term care and personalized rehabilitation. However, the pathophysiology of acute and post-acute manifestations of COVID-19 is still under study, as a better comprehension of these mechanisms would ensure more effective personalized therapies. To date, mounting evidence suggests a crucial endothelial contribution to the clinical manifestations of COVID-19, as endothelial cells appear to be a direct or indirect preferential target of the virus. Thus, the dysregulation of many of the homeostatic pathways of the endothelium has emerged as a hallmark of severity in COVID-19. The aim of this review is to summarize the pathophysiology of endothelial dysfunction in COVID-19, with a focus on personalized pharmacological and rehabilitation strategies targeting endothelial dysfunction as an attractive therapeutic option in this clinical setting.

The impact of different forms of exercise on endothelial progenitor cells in healthy populations

Circulating endothelial progenitor cells (EPCs) contribute to vascular healing and neovascularisation, while exercise is an effective means to mobilise EPCs into the circulation.

OBJECTIVES

to systematically examine the acute and chronic effects of different forms of exercise on circulating EPCs in healthy populations.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed.

RESULTS

thirty-one articles met the inclusion criteria including 747 participants aged 19 to 76 years. All included trials used flow cytometry for identification of circulating EPCs. Eight and five different EPC phenotypes were identified in the acute and chronic trials, respectively. In the acute trials, moderate intensity continuous (MICON), maximal, prolonged endurance, resistance and high intensity interval training (HIIT) exercise protocols were utilised. Prolonged endurance and resistance exercise had the most profound effect on circulating EPCs followed by maximal exercise. In the chronic trials, MICON exercise, HIIT, HIIT compared to MICON and MICON compared to exergame (exercise modality based on an interactive video game) were identified. MICON exercise had a positive effect on circulating EPCs in older sedentary individuals which was accompanied by improvements in endothelial function and arterial stiffness. Long-stage HIIT (4 min bouts) appears to be an effective means and superior than MICON exercise in mobilising circulating EPCs. In conclusion, both in acute and chronic trials the degree of exercise-induced EPC mobilisation depends upon the exercise regime applied. In future, more research is warranted to examine the dose-response relationship of different exercise forms on circulating EPCs using standardised methodology and EPC phenotype.

Cardiopulmonary Exercise Performance and Endothelial Function in Convalescent COVID-19 Patients

Background: Endothelial dysfunction has been proposed as the common pathogenic background of most manifestations of coronavirus disease 2019 (COVID-19). Among these, some authors also reported an impaired exercise response during cardiopulmonary exercise testing (CPET). We aimed to explore the potential association between endothelial dysfunction and the reduced CPET performance in COVID-19 survivors. Methods: 36 consecutive COVID-19 survivors underwent symptom-limited incremental CPET and assessment of endothelium-dependent flow-mediate dilation (FMD) according to standardized protocols. Results: A significantly higher FMD was documented in patients with a preserved, as compared to those with a reduced, exercise capacity (4.11% ± 2.08 vs. 2.54% ± 1.85, p = 0.048), confirmed in a multivariate analysis (β = 0.899, p = 0.038). In the overall study population, FMD values showed a significant Pearson’s correlation with two primary CPET parameters, namely ventilation/carbon dioxide production (VE/VCO₂) slope (r = −0.371, p = 0.026) and end-tidal carbon dioxide tension (P_ETCO₂) at peak (r = 0.439, p = 0.007). In multiple linear regressions, FMD was the only independent predictor of VE/VCO₂ slope (β = −1.308, p = 0.029) and peak P_ETCO₂ values (β = 0.779, p = 0.021). Accordingly, when stratifying our study population based on their ventilatory efficiency, patients with a ventilatory class III-IV (VE/VCO₂ slope ≥ 36) exhibited significantly lower FMD values as compared to those with a ventilatory class I-II. Conclusions: The alteration of endothelial barrier properties in systemic and pulmonary circulation may represent a key pathogenic mechanism of the reduced CPET performance in COVID-19 survivors. Personalized pharmacological and rehabilitation strategies targeting endothelial function may represent an attractive therapeutic option.

Exercise and Carotid Properties in the Young-The KiGGS-2 Study

Background: Carotid intima-media thickness (cIMT) and stiffness (cS) are predictive markers of early vascular aging and atherosclerotic risk. This study assessed, whether exercise has protective effects on carotid structure and function or on vascular risk in the young. Methods: Volume and change of exercise (recreational and organized sports participation) of German adolescents and young adults was assessed within the prospective population-study KiGGS at KiGGS-Wave-1 (2009-2012) and KiGGS-Wave-2 (2014-2017) using standardized self-reporting questionnaires. CIMT and cS were measured by real-time B-mode ultrasound sequences with semi-automated edge-detection and automatic electrocardiogram-gated quality control in 2,893 participants (14-28 years, 49.6% female). A cumulative index for atherosclerotic risk (CV-R) included z-scores of mean arterial pressure, triglycerides, total/HDL-cholesterol-ratio, body mass index, and HbA1c. Results: At KiGGS-Wave-2 cross-sectional CV-R but not cS and cIMT was lower in all exercise-groups compared to "no exercise" (B = -0.73, 95%-CI = -1.26 to 0.19, p = 0.008). Longitudinal volume of exercise was negatively associated with CV-R (B = -0.37, 95%-CI = -0.74 to 0.00, p = 0.048) but not with cS and cIMT. Cross-sectional relative risk of elevated CV-R but not cS and cIMT was lower in all exercise-groups compared to "no exercise" (RR = 0.80, 95%-CI = 0.66 to 0.98, p = 0.033). High exercise volumes were associated with lower relative risk of elevated CV-R (RR = 0.80, 95%-CI = 0.65-0.97, p = 0.021) and cS in tendency but not with cIMT. Conclusions: Increased levels of exercise are associated with a better cardiovascular risk profile in young individuals, but not with cS and cIMT. Our study confirms previous recommendations on exercise in this age group without demonstrating a clear benefit on surrogate markers of vascular health.

Exercise as a Peripheral Circadian Clock Resynchronizer in Vascular and Skeletal Muscle Aging

Aging is characterized by several progressive physiological changes, including changes in the circadian rhythm. Circadian rhythms influence behavior, physiology, and metabolic processes in order to maintain homeostasis; they also influence the function of endothelial cells, smooth muscle cells, and immune cells in the vessel wall. A clock misalignment could favor vascular damage and indirectly also affect skeletal muscle function. In this review, we focus on the dysregulation of circadian rhythm due to aging and its relationship with skeletal muscle changes and vascular health as possible risk factors for the development of sarcopenia, as well as the role of physical exercise as a potential modulator of these processes.

Alisol A 24-acetate protects oxygen-glucose deprivation-induced brain microvascular endothelial cells against apoptosis through miR-92a-3p inhibition by targeting the B-cell lymphoma-2 gene

CONTEXT

Alisol A 24-acetate has been used to treat vascular diseases. However, the underlying mechanisms still remain unclear.

OBJECTIVE

The present study evaluated the antiapoptotic effect of alisol A 24-acetate on brain microvascular endothelial cells (BMECs) and explored the underlying mechanisms.

MATERIALS AND METHODS

BMECs were injured through oxygen -glucose deprivation (OGD) after alisol A 24-acetate treatment. Cell viability and half-maximal inhibitory concentration (IC₅₀) were measured using CCK-8, whereas inflammatory factors and oxidative stress indicators were measured using enzyme linked immunosorbent assay. Cell invasion and wound healing assays were detected. Cell apoptosis was assessed using flow cytometry. B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X (Bax) expression were analyzed using Western blotting. Dual-luciferase assay was applied to detect target genes of miR-92a-3p.

RESULT

Alisol A 24-acetate had an IC₅₀ of 98.53 mg/L and inhibited cell viability at concentrations over 50mg/L. OGD induced apoptosis and promoted miR-92a-3p overexpression in BMECs. However, alisol A 24-acetate treatment suppressed inflammation, improved migration and invasion abilities, increased Bcl-2 expression, inhibited Bax expression, and repressed apoptosis and miR92a-3p overexpression in OGD-induced BMECs. MiR-92a-3p overexpression promoted cell apoptosis and suppressed Bcl-2 expression, whereas its inhibitor reversed the tendency. Alisol A 24-acetate treatment relieved the effects of miR-92a-3p overexpression. Dual-luciferase assay confirmed that miR-92a-3p negatively regulated the Bcl-2 expression.

CONCLUSIONS

These findings suggest that alisol A 24-acetate exerts antiapoptotic effects on OGD-induced BMECs through miR-92a-3p inhibition by targeting the Bcl-2 gene, indicating its potential for BMECs protection and as a novel therapeutic agent for the treatment of cerebrovascular disease.

Effect of dehydroepiandrosterone on atherosclerosis in postmenopausal women

In China, cardiovascular disease (CVD) has surpassed malignant tumours to become the disease with the highest mortality rate, and atherosclerosis (AS) is an important pathological cause of CVD. Dehydroepiandrosterone (DHEA) is the most abundant steroid hormone in circulating human blood and is a precursor of estrogen and androgen. DHEA is converted into a series of sex hormones in local peripheral tissues where its acts physiologically. DHEA also acts therapeutically, thereby avoiding the adverse systemic reactions to sex hormones. DHEA inhibits AS, thus inhibiting the development of CVD, and it improves the prognosis for CVD. The incidence of CVD in postmenopausal women is substantially higher than that in premenopausal women, and that incidence is believed to be related to a decrease in ovarian function. The current review analyzes the mechanisms of postmenopausal women's susceptibility to AS. They tend to have dyslipidemia, and their vascular smooth muscle cells (VSMCs) proliferate and migrate more. In addition, oxidative stress and the inflammatory response of endothelial cells (ECs) are more serious in postmenopausal women. This review also discusses how DHEA combats AS by countering these mechanisms, which include regulating the blood lipid status, protecting ECs (including coping with oxidative stress and inflammatory reactions of the vascular endothelium, inhibiting apoptosis of ECs, and inducing NO production) and inhibiting the proliferation and migration of VSMCs. As a result, DHEA has great value in preventing AS and inhibiting its progression in postmenopausal women.

Breast cancer chemotherapy vascular toxicity: a review of mediating mechanisms and exercise as a potential therapeutic

Breast cancer chemotherapy, although very potent against tumour tissue, results in significant cardiovascular toxicity. The focus of research in this area has been predominantly towards cardiotoxicity. There is limited evidence detailing the impact of such treatment on the vasculature despite its central importance within the cardiovascular system and resultant detrimental effects of damage and dysfunction. This review highlights the impact of chemotherapy for breast cancer on the vascular endothelium. We consider the most likely mechanisms of endothelial toxicity to be through direct damage and dysfunction of the endothelium. There are sharp consequences of these detrimental effects as they can lead to cardiovascular disease. However, there is potential for exercise to alleviate some of the vascular toxicity of chemotherapy, and the evidence for this is provided. The potential role of exercise in protecting against vascular toxicity is explained, highlighting the recent in-human and animal model exercise interventions. Lastly, the mediating mechanisms of exercise protection of endothelial health is discussed, focusing on the importance of exercise for endothelial health, function, repair, inflammation and hyperlipidaemia, angiogenesis, and vascular remodelling. These are all important counteracting measures against chemotherapy-induced toxicity and are discussed in detail.

LncRNA GAS5 Silencing Attenuates Oxygen-Glucose Deprivation/Reperfusion-Induced Injury in Brain Microvascular Endothelial Cells via miR-34b-3p-Dependent Regulation of EPHA4

BACKGROUND

The aim of our study was to explore the role of long non-coding RNA (lncRNA) growth arrest-specific 5 (GAS5) in ischemic stroke using oxygen-glucose deprivation/reperfusion (OGD/R)-induced bEnd.3 cells as in vitro cell model.

METHODS

Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot assay were adopted to analyze RNA and protein expression. Cell viability and apoptosis were analyzed by Cell Counting Kit-8 (CCK8) assay and flow cytometry. The levels of nitric oxide (NO) and endothelin-1 (ET-1) in culture supernatant were examined by their matching commercial kits. The intermolecular target interaction was predicted by starBase software and tested by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay.

RESULTS

OGD/R-induced apoptosis and dysregulation in vascular endocrine system were largely alleviated by the knockdown of GAS5. GAS5 interacted with microRNA-34b-3p (miR-34b-3p), and GAS5 silencing protected bEnd.3 cells from OGD/R-induced injury partly through up-regulating miR-34b-3p. EPH receptor A4 (EPHA4) was a target of miR-34b-3p. GAS5 acted as the molecular sponge of miR-34b-3p to up-regulate EPHA4 in bEnd.3 cells. GAS5 interference protected against OGD/R-induced damage in bEnd.3 cells partly through down-regulating EPHA4.

CONCLUSION

LncRNA GAS5 knockdown protected brain microvascular endothelial cells bEnd.3 from OGD/R-induced injury depending on the regulation of miR-34b-3p/EPHA4 axis.

Short term chronic toxicity of tributyltin on the testes of adult albino rats and the possible protective role of omega-3

The declining rate of male fertility is a growing concern. Tributyltin (TBT) is a well-known endocrine disruptor (ED), that induces imposex in female gastropods and is widely used in various industrial applications. The aim of this study was to evaluate the toxic effects of TBT on the testes of adult albino rats and the possible role of omega-3. Forty two adult male albino rats were divided into five groups; control group (Group I) and four experimental groups: omega-3 treated group, TBT treated group, TBT & omega-3 treated group and follow up group. At the end of the study, the rats were subjected to biochemical, histological, immunohistochemical staining for Ki-67 and seminal examinations. Our results clarfied that TBT induced a significant decrease in testosterone, FSH, LH and serum glutathione peroxidase levels and a significant increase in the serum Malondialdehyde as compared to the control group. Tributyltin induced disorganization and shrinkage of seminiferous tubules, apoptosis, cellular damage and marked reduction in the germinal epithelium. A significant decrease in the cell proliferation and arrested spermatogenesis were also detected. Seminal analysis of TBT group showed a significant affection of all parameters as compared to other groups. Omega-3 ameliorated all of these hazardous effects. Follow up group still showed toxic effects. In conclusion, TBT has a toxic effect on the testis. Increased testicular oxidative stress, cellular damage and arrest of spermatogenesis with attenuation in antioxidant defenses are all contributing factors. Omega-3 can protect against TBT induced reproductive toxicity.

Establishment of optimal exercise therapy using near-infrared spectroscopy monitoring of tissue muscle oxygenation after therapeutic angiogenesis for patients with critical limb ischemia: A multicenter, randomized, controlled trial

Critical limb ischemia (CLI) is a potentially life-threatening condition that involves severely reduced blood flow to the peripheral arteries due to arteriosclerosis obliterans (ASO) of the limbs or a similar condition. CLI patients must undergo revascularization to avoid amputation of the lower limbs and improve their survival prognosis. However, the outcomes of conventional surgical revascularization or endovascular therapy are inadequate; therefore, establishing further effective treatment methods is an urgent task. We perform therapeutic angiogenesis using autologous bone marrow-derived mononuclear cells in clinical practice and demonstrated its safety and efficacy for CLI patients for whom conventional treatments failed or are not indicated. Exercise therapies must be devised for CLI patients who have undergone therapeutic angiogenesis to save their limbs and improve survival. Because evidence regarding the efficacy and safety of exercise therapy for CLI patients is lacking, we plan to perform a prospective trial of the efficacy and safety of optimal exercise therapy following therapeutic angiogenesis for CLI patients.

The trial will enroll 30 patients between 20 and 79 years with Rutherford category 4 or 5 CLI caused by ASO who will undergo therapeutic angiogenesis. Participants will be randomly allocated to receive either optimal exercise therapy or fixed exercise therapy. Those receiving optimal exercise therapy will undergo tissue muscle oxygen saturation monitoring using near-infrared spectroscopy while performing exercises and will be prescribed optimal exercise therapy. The optimal amount of exercise will be determined on day 8, 31, 61, 91 and 181 after therapeutic angiogenesis.

Ethics and dissemination

This protocol was approved by the Institutional Review Boards of Kyoto Prefectural University of Medicine. In accordance with the Helsinki Declaration, written informed consent has been obtained from all participants prior to enrollment. The results of this trial will be disseminated by publication in a peer-reviewed journal.

Trial registration

This trial is registered at http://www.umin.ac.jp/ctr/index.htm (identifier: UMIN000035288).

The role of age in determining the effects of lipo-PGE1 infusion on immediate arterial maximal flow velocity in patients with diabetes undergoing free flap surgery for lower extremity reconstruction: A prospective observational study

BACKGROUND

Diabetes mellitus may have a negative effect on free flap perfusion in patients undergoing reconstructive surgery. Little is known of the effects of lipo-prostaglandin E1 (lipo-PGE1) on flap blood flow in diabetes. This study investigated the effects of lipo-PGE1 on maximal blood flow velocity of the free flap arterial pedicle in patients with diabetes.

METHODS

This prospective observational study assessed maximal blood flow velocity in the arterial pedicle before and 30 min after infusion of 0.4 μg/h lipo-PGE1 in 40 patients with diabetes who received a free flap for lower extremity reconstruction. Multivariate logistic regression analysis was performed to determine whether age, hemoglobin A1c concentration, duration of diabetes, and flap type were significantly associated with increased maximal blood flow velocity after lipo-PGE1 infusion or not.

RESULTS

The maximal blood flow velocity of the free flap did not differ significantly before and 30 min after lipo-PGE1 infusion. Multivariate logistic regression analysis showed that age <65 years was the only independent factor associated with increased maximal blood flow velocity after lipo-PGE1 infusion (odds ratio = 5.344; p = 0.022).

CONCLUSION

Assessments of all patients with diabetes undergoing free flap surgery, when age was not taken into consideration, found that lipo-PGE1 did not significantly increase the maximal blood flow velocity of the free flap arterial pedicle. However, when age was taken into consideration, lipo-PGE1 increased blood flow velocity in patients <65 years old, suggesting that age influences the effect of lipo-PGE1 on the blood flow velocity.

Personalized Cardiovascular Regenerative Medicine: Targeting the Extreme Stages of Life

Cardiovascular regenerative medicine is an exciting new approach that promises to change the current care of million people world-wide. Major emphasis was given to the quality and quantities of regenerative products, but recent evidence points to the importance of a better specification of the target population that may take advantage of these advanced medical treatments. Patient stratification is an important step in drug development. Tailoring treatment to the patient's specificity allowed significant improvement in cancer therapy, but personalized regenerative medicine is still at the initial stage in the cardiovascular field. For example, new-borns with a congenital heart condition and elderly people require dedicated therapeutic approaches, which adapt to their lifetime needs. In these people, personalized treatments may overcome the benefits delivered by standard protocols. In this review, we provide insights into these extreme stages of life as potential targets for cardiovascular reconstitution.

Combination of exercise training and L-arginine reverses aging process through suppression of oxidative stress, inflammation, and apoptosis in the rat heart

Aging-induced progressive decline of molecular and metabolic factors in the myocardium is suggested to be related with heart dysfunction and cardiovascular disease. Therefore, we evaluated the effects of exercise training and L-arginine supplementation on oxidative stress, inflammation, and apoptosis in ventricle of the aging rat heart. Twenty-four 24-month-aged Wistar rats were randomly divided into four groups: the aged control, aged exercise, aged L-arginine (orally administered with 150 mg/kg for 12 weeks), and aged exercise + L-arginine groups. Six 4-month-old rats were also considered the young control. Animals with training program performed exercise on a treadmill 5 days/week for 12 weeks. After 12 weeks, protein levels of Bax, Bcl-2, pro-caspase-3/cleaved caspase-3, cytochrome C, and heat shock protein (HSP)-70 were assessed. Tissue contents of total anti-oxidant capacity, superoxide dismutase, catalase, and levels of tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, and IL-6 were analyzed. Histological and fibrotic changes were also evaluated. Treadmill exercise and L-arginine supplementation significantly alleviated aging-induced apoptosis with enhancing HSP-70 expression, increasing anti-oxidant enzyme activity, and suppressing inflammatory markers in the cardiac myocytes. Potent attenuation in apoptosis, inflammation, and oxidative stress was indicated in the rats with the combination of L-arginine supplementation and exercise program in comparison with each group (p < 0.05). In addition, fibrosis percentage and collagen accumulation were significantly lower in the rats with the combination treatment of L-arginine and exercise (p < 0.05). Treadmill exercise and L-arginine supplementation provided protection against age-induced increase in the myocyte loss and formation of fibrosis in the ventricle through potent suppression of oxidative stress, inflammations, and apoptosis pathways.

Heart Failure With Preserved Ejection Fraction: A Review of Cardiac and Noncardiac Pathophysiology

Heart failure with preserved ejection fraction (HFpEF) is one of the largest unmet clinical needs in 21st-century cardiology. It is a complex disorder resulting from the influence of several comorbidities on the endothelium. A derangement in nitric oxide bioavailability leads to an intricate web of physiological abnormalities in the heart, blood vessels, and other organs. In this review, we examine the contribution of cardiac and noncardiac factors to the development of HFpEF. We zoom in on recent insights on the role of comorbidities and microRNAs in HFpEF. Finally, we address the potential of exercise training, which is currently the only available therapy to improve aerobic capacity and quality of life in HFpEF patients. Unraveling the underlying mechanisms responsible for this improvement could lead to new biomarkers and therapeutic targets for HFpEF.

Endothelial Regenerative Capacity and Aging: Influence of Diet, Exercise and Obesity

Background:

The endothelium plays an important role in cardiovascular regulation, from blood flow to platelet aggregation, immune cell infiltration and demargination. A dysfunctional endo-thelium leads to the onset and progression of Cardiovascular Disease (CVD). The aging endothelium displays significant alterations in function, such as reduced vasomotor functions and reduced angio-genic capabilities. This could be partly due to elevated levels of oxidative stress and reduced endothe-lial cell turnover. Circulating angiogenic cells, such as Endothelial Progenitor Cells (EPCs) play a significant role in maintaining endothelial health and function, by supporting endothelial cell prolifera-tion, or via incorporation into the vasculature and differentiation into mature endothelial cells. Howev-er, these cells are reduced in number and function with age, which may contribute to the elevated CVD risk in this population. However, lifestyle factors, such as exercise, physical activity obesity, and dietary intake of omega-3 polyunsaturated fatty acids, nitrates, and antioxidants, significantly af-fect the number and function of these circulating angiogenic cells.

Conclusion:

This review will discuss the effects of advancing age on endothelial health and vascular regenerative capacity, as well as the influence of diet, exercise, and obesity on these cells, the mecha-nistic links and the subsequent impact on cardiovascular health

Endothelial Progenitor Cells: New Targets for Therapeutics for Inflammatory Conditions With High Cardiovascular Risk

Over the past decade, we have witnessed an exponential growth of interest into the role of endothelial progenitor cells (EPCs) in cardiovascular disease. While the major thinking revolves around EPC angiogenic repair properties, we have used a hypothesis-driven approach to discover disease-related defects in their characteristics and based on these findings, have identified opportunities for functional enhancement, which offer an exciting avenue for translation into clinical intervention. In this review, we focus on two groups; circulating myeloid angiogenic cells (MACs) and late outgrowth endothelial colony forming cells (ECFCs), and will discuss the unique properties and defects of each population, as new insights have been gained into the potential function of each sub-type using current techniques and multiomic technology. We will discuss their role in inflammatory disorders and alterations in mitochondrial function. In addition, we share key insights into the glycocalyx, and propose this network of membrane-bound proteoglycans and glycoproteins, covering the endothelium warrants further investigation in order to clarify its significance in ECFC regulation of vascularization and angiogenesis and ultimately for potential translational therapeutic aspects.

Role of glutathione biosynthesis in endothelial dysfunction and fibrosis

Glutathione (GSH) biosynthesis is essential for cellular redox homeostasis and antioxidant defense. The rate-limiting step requires glutamate-cysteine ligase (GCL), which is composed of the catalytic (GCLc) and the modulatory (GCLm) subunits. To evaluate the contribution of GCLc to endothelial function we generated an endothelial-specific Gclc haplo-insufficient mouse model (Gclc e/+ mice). In murine lung endothelial cells (MLEC) derived from these mice we observed a 50% reduction in GCLc levels compared to lung fibroblasts from the same mice. MLEC obtained from haplo-insufficient mice showed significant reduction in GSH levels as well as increased basal and stimulated ROS levels, reduced phosphorylation of eNOS (Ser 1177) and increased eNOS S-glutathionylation, compared to MLEC from wild type (WT) mice. Studies in mesenteric arteries demonstrated impaired endothelium-dependent vasodilation in Gclc(e/+) male mice, which was corrected by pre-incubation with GSH-ethyl-ester and BH4. To study the contribution of endothelial GSH synthesis to renal fibrosis we employed the unilateral ureteral obstruction model in WT and Gclc(e/+) mice. We observed that obstructed kidneys from Gclc(e/+) mice exhibited increased deposition of fibrotic markers and reduced Nrf2 levels. We conclude that the preservation of endothelial GSH biosynthesis is not only critical for endothelial function but also in anti-fibrotic responses.

Getting Old through the Blood: Circulating Molecules in Aging and Senescence of Cardiovascular Regenerative Cells

Global aging is a hallmark of our century. The natural multifactorial process resulting in aging involves structural and functional changes, affecting molecules, cells, and tissues. As the western population is getting older, we are witnessing an increase in the burden of cardiovascular events, some of which are known to be directly linked to cellular senescence and dysfunction. In this review, we will focus on the description of a few circulating molecules, which have been correlated to life span, aging, and cardiovascular homeostasis. We will review the current literature concerning the circulating levels and related signaling pathways of selected proteins (insulin-like growth factor 1, growth and differentiation factor-11, and PAI-1) and microRNAs of interest (miR-34a, miR-146a, miR-21), whose bloodstream levels have been associated to aging in different organisms. In particular, we will also discuss their potential role in the biology and senescence of cardiovascular regenerative cell types, such as endothelial progenitor cells, mesenchymal stromal cells, and cardiac progenitor cells.

Effects of acute exercise on endothelial function in patients with abdominal aortic aneurysm

Endothelial dysfunction is observed in patients with abdominal aortic aneurysm (AAA), who have increased risk of cardiovascular events and mortality. This study aimed to assess the acute effects of moderate- and higher-intensity exercise on endothelial function, as assessed by flow-mediated dilation (FMD), in AAA patients (74 ± 6 yr old, n = 22) and healthy adults (72 ± 5 yr old, n = 22). Participants undertook three randomized visits, including moderate-intensity continuous exercise [40% peak power output (PPO)], higher-intensity interval exercise (70% PPO), and a no-exercise control. Brachial artery FMD was assessed at baseline and at 10 and 60 min after each condition. Baseline FMD was lower [by 1.10% (95% confidence interval: 0.72-.81), P = 0.044] in AAA patients than in healthy adults. There were no group differences in FMD responses after each condition ( P = 0.397). FMD did not change after no-exercise control but increased by 1.21% (95% confidence interval: 0.69-1.73, P < 0.001) 10 min after moderate-intensity continuous exercise in both groups and returned to baseline after 60 min. Conversely, FMD decreased by 0.93% (95% confidence interval: 0.41-1.44, P < 0.001) 10 min after higher-intensity interval exercise in both groups and remained decreased after 60 min. We found that the acute response of endothelial function to exercise is intensity-dependent and similar between AAA patients and healthy adults. Our findings provide evidence that regular exercise may improve vascular function in AAA patients, as it does in healthy adults. Improved FMD after moderate-intensity exercise may provide short-term benefit. Whether the decrease in FMD after higher-intensity exercise represents an additional risk and/or a greater stimulus for vascular adaptation remains to be elucidated. NEW & NOTEWORTHY Abdominal aortic aneurysm patients have vascular dysfunction. We observed a short-term increase in vascular function after moderate-intensity exercise. Conversely, higher-intensity exercise induced a prolonged reduction in vascular function, which may be associated with both short-term increases in cardiovascular risk and signaling for longer-term vascular adaptation in abdominal aortic aneurysm patients.

Biogenesis of Pro-senescent Microparticles by Endothelial Colony Forming Cells from Premature Neonates is driven by SIRT1-Dependent Epigenetic Regulation of MKK6

Senescent cells may exert detrimental effect on microenvironment through the secretion of soluble factors and the release of extracellular vesicles, such as microparticles, key actors in ageing and cardiovascular diseases. We previously reported that sirtuin-1 (SIRT1) deficiency drives accelerated senescence and dysfunction of endothelial colony-forming cells (ECFC) in PT neonates. Because preterm birth (PT) increases the risk for cardiovascular diseases during neonatal period as well as at adulthood, we hypothesized that SIRT1 deficiency could control the biogenesis of microparticles as part of a senescence–associated secretory phenotype (SASP) of PT-ECFC and investigated the related molecular mechanisms. Compared to control ECFC, PT-ECFC displayed a SASP associated with increased release of endothelial microparticles (EMP), mediating a paracrine induction of senescence in naïve endothelial cells. SIRT1 level inversely correlated with EMP release and drives PT-ECFC vesiculation. Global transcriptomic analysis revealed changes in stress response pathways, specifically the MAPK pathway. We delineate a new epigenetic mechanism by which SIRT1 deficiency regulates MKK6/p38^MAPK/Hsp27 pathway to promote EMP biogenesis in senescent ECFC. These findings deepen our understanding of the role of ECFC senescence in the disruption of endothelial homeostasis and provide potential new targets towards the control of cardiovascular risk in individuals born preterm.

Aging: Molecular Pathways and Implications on the Cardiovascular System

The world's population over 60 years is growing rapidly, reaching 22% of the global population in the next decades. Despite the increase in global longevity, individual healthspan needs to follow this growth. Several diseases have their prevalence increased by age, such as cardiovascular diseases, the leading cause of morbidity and mortality worldwide. Understanding the aging biology mechanisms is fundamental to the pursuit of cardiovascular health. In this way, aging is characterized by a gradual decline in physiological functions, involving the increased number in senescent cells into the body. Several pathways lead to senescence, including oxidative stress and persistent inflammation, as well as energy failure such as mitochondrial dysfunction and deregulated autophagy, being ROS, AMPK, SIRTs, mTOR, IGF-1, and p53 key regulators of the metabolic control, connecting aging to the pathways which drive towards diseases. In addition, senescence can be induced by cellular replication, which resulted from telomere shortening. Taken together, it is possible to draw a common pathway unifying aging to cardiovascular diseases, and the central point of this process, senescence, can be the target for new therapies, which may result in the healthspan matching the lifespan.

Targeting vascular (endothelial) dysfunction

Cardiovascular diseases are major contributors to global deaths and disability-adjusted life years, with hypertension a significant risk factor for all causes of death. The endothelium that lines the inner wall of the vasculature regulates essential haemostatic functions, such as vascular tone, circulation of blood cells, inflammation and platelet activity. Endothelial dysfunction is an early predictor of atherosclerosis and future cardiovascular events. We review the prognostic value of obtaining measurements of endothelial function, the clinical techniques for its determination, the mechanisms leading to endothelial dysfunction and the therapeutic treatment of endothelial dysfunction. Since vascular oxidative stress and inflammation are major determinants of endothelial function, we have also addressed current antioxidant and anti-inflammatory therapies. In the light of recent data that dispute the prognostic value of endothelial function in healthy human cohorts, we also discuss alternative diagnostic parameters such as vascular stiffness index and intima/media thickness ratio. We also suggest that assessing vascular function, including that of smooth muscle and even perivascular adipose tissue, may be an appropriate parameter for clinical investigations.

LINKED ARTICLES

This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc.

Acarbose Accelerates Wound Healing via Akt/eNOS Signaling in db/db Mice

Refractory wound is a dreaded complication of diabetes and is highly correlated with EPC dysfunction caused by hyperglycemia. Acarbose is a widely used oral glucose-lowering drug exclusively for T2DM. Previous studies have suggested the beneficial effect of acarbose on improving endothelial dysfunction in patients with T2DM. However, no data have been reported on the beneficial efficacy of acarbose in wound healing impairment caused by diabetes. We herein investigated whether acarbose could improve wound healing in T2DM db/db mice and the possible mechanisms involved. Acarbose hastened wound healing and enhanced angiogenesis, accompanied by increased circulating EPC number in db/db mice. In vitro, a reversed BM-EPC dysfunction was observed after the administration of acarbose in db/db mice, as reflected by tube formation assay. In addition, a significantly increased NO production was also witnessed in BM-EPCs from acarbose treated db/db mice, with decreased O₂ levels. Akt inhibitor could abolish the beneficial effect of acarbose on high glucose induced EPC dysfunction in vitro, accompanied by reduced eNOS activation. Acarbose displayed potential effect in promoting wound healing and improving angiogenesis in T2DM mice, which was possibly related to the Akt/eNOS signaling pathway.

Kinetics of circulating progenitor cell mobilization during submaximal exercise

Circulating progenitor cells (CPCs) are a heterogeneous population of stem/progenitor cells in peripheral blood that includes hematopoietic stem and progenitor cells (HSPCs and HSCs), endothelial progenitor cells (EPCs), and mesenchymal stem cells (MSCs) that are involved in tissue repair and adaptation. CPC mobilization during exercise remains uncharacterized in young adults. The purpose of this study was to investigate the kinetics of CPC mobilization during and after submaximal treadmill running and their relationship to mobilization factors. Seven men [age = 25.3 ± 2.4 yr, body mass index = 23.5 ± 1.0 kg/m2, peak O2uptake (V̇o2peak) = 60.9 ± 2.74 ml·kg−1·min−1] ran on a treadmill for 60 min at 70% V̇o2peak. Blood sampling occurred before (Pre), during [20 min (20e), 40 min (40e), 60 min (60e)], and after exercise [15 min (15p), 60 min (60p), 120 min (120p)] for quantification of CPCs (CD34+), HSPCs (CD34+/CD45low), HSCs (CD34+/CD45low/CD38−), CD34+MSCs (CD45−/CD34+/CD31−/CD105+), CD34−MSCs (CD45−/CD34−/CD31−/CD105+), and EPCs (CD45−/CD34+/CD31+) via flow cytometry. CPC concentration increased compared with Pre at 20e and 40e (2.7- and 2.4-fold, respectively, P < 0.05). HSPCs and HSCs increased at 20e compared with 60p (2.7- and 2.8-fold, respectively, P < 0.05), whereas EPCs and both MSC populations did not change. CXC chemokine ligand (CXCL) 12 (1.5-fold; P < 0.05) and stem cell factor (1.3-fold; P < 0.05) were increased at 40e and remained elevated postexercise. The peak increase in CPCs was positively correlated to concentration of endothelial cells during exercise with no relationship to CXCL12 and SCF. Our data show the kinetics of progenitor cell mobilization during exercise that could provide insight into cellular mediators of exercise-induced adaptations, and have implication for the use of exercise as an adjuvant therapy for CPC collection in hematopoietic stem cell transplant.

NEW & NOTEWORTHY Using a comprehensive evaluation of circulating progenitor cells (CPCs), we show that CPC mobilization during exercise is related to tissue damage, and not plasma concentrations of CXC chemokine ligand 12 and stem cell factor. These data have implications for the use of exercise interventions as adjuvant therapy for CPC mobilization in the context of hematopoietic stem cell transplant and also support the role of mobilized progenitor cells as cellular mediators of systemic adaptations to exercise.

Identification of cardiovascular risk factors associated with bone marrow cell subsets in patients with STEMI: a biorepository evaluation from the CCTRN TIME and LateTIME clinical trials

Autologous bone marrow mononuclear cell (BM-MNC) therapy for patients with ST-segment elevation myocardial infarction (STEMI) has produced inconsistent results, possibly due to BM-MNC product heterogeneity. Patient-specific cardiovascular risk factors (CRFs) may contribute to variations in BM-MNC composition. We sought to identify associations between BM-MNC subset frequencies and specific CRFs in STEMI patients. Bone marrow was collected from 191 STEMI patients enrolled in the CCTRN TIME and LateTIME trials. Relationships between BM-MNC subsets and CRFs were determined with multivariate analyses. An assessment of CRFs showed that hyperlipidemia and hypertension were associated with a higher frequency of CD11b+ cells (P = 0.045 and P = 0.016, respectively). In addition, we found that females had lower frequencies of CD11b+ (P = 0.018) and CD45+CD14+ (P = 0.028) cells than males, age was inversely associated with the frequency of CD45+CD31+ cells (P = 0.001), smoking was associated with a decreased frequency of CD45+CD31+ cells (P = 0.013), glucose level was positively associated with the frequency of CD45+CD3+ cells, and creatinine level (an indicator of renal function) was inversely associated with the frequency of CD45+CD3+ cells (P = 0.015). In conclusion, the frequencies of monocytic, lymphocytic, and angiogenic BM-MNCs varied in relation to patients' CRFs. These phenotypic variations may affect cell therapy outcomes and might be an important consideration when selecting patients for and reviewing results from autologous cell therapy trials.

TDB protects vascular endothelial cells against oxygen-glucose deprivation/reperfusion-induced injury by targeting miR-34a to increase Bcl-2 expression

Prolonged ischemia can result in apoptotic death of vascular endothelial cells and lead to ischemic vascular diseases including vascular dementia, arteriosclerosis and brain oedema. Finding protective strategies to prevent this is therefore an urgent mission. Recent studies have shown that dysregulation of microRNAs (miRNAs) can lead to imbalance of Bcl-2 family proteins and mitochondrial dysfunction, leading to further damage of vascular cells under ischemic conditions. However, whether miRNAs can be used as a drug target for treating vascular diseases is not fully understood. In this study, we observed that the natural product 2,4,5-trihydroxybenzaldehyde (TDB) could effectively inhibit vascular cell apoptosis following oxygen-glucose deprivation/reperfusion (OGD/R) by maintaining mitochondrial membrane potential (MMP) and suppressing activation of the mitochondria-dependent caspase-9/3 apoptosis pathway. Furthermore, we identified miR-34a, a crucial negative regulator of Bcl-2, as a target for the protective effect of TDB on vascular cells. TDB-induced suppression of miR-34a resulted in a significant upregulation of Bcl-2 protein, MMP maintenance, and the survival of vascular cells following OGD/R. Our findings suggest that targeting miR-34a with the natural product TDB may provide a novel strategy for the treatment of ischemic vascular injuries, and demonstrate the therapeutic potential in targeting miRNAs using appropriate small molecules.