Racial Differences in Blood Pressure Control Following Stroke: The REGARDS Study.

BACKGROUND AND PURPOSE: In the general population, Black adults are less likely than White adults to have controlled blood pressure (BP), and when not controlled, they are at greater risk for stroke compared with White adults. High BP is a major modifiable risk factor for recurrent stroke, but few studies have examined racial differences in BP control among stroke survivors. METHODS: We used data from the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) to examine disparities in BP control between Black and White adults, with and without a history of stroke. We studied participants taking antihypertensive medication who did and did not experience an adjudicated stroke (n=306 and 7693 participants, respectively) between baseline (2003-2007) and a second study visit (2013-2016). BP control at the second study visit was defined as systolic BP <130 mm Hg and diastolic BP <80 mm Hg except for low-risk adults ≥65 years of age (ie, those without diabetes, chronic kidney disease, history of cardiovascular disease, and with a 10-year predicted atherosclerotic cardiovascular disease risk <10%) for whom BP control was defined as systolic BP <130 mm Hg. RESULTS: Among participants with a history of stroke, 50.3% of White compared with 39.3% of Black participants had controlled BP. Among participants without a history of stroke, 56.0% of White compared with 50.2% of Black participants had controlled BP. After multivariable adjustment, there was a tendency for Black participants to be less likely than White participants to have controlled BP (prevalence ratio, 0.77 [95% CI, 0.59-1.02] for those with a history of stroke and 0.92 [95% CI, 0.88-0.97] for those without a history of stroke). CONCLUSIONS: There was a lower proportion of controlled BP among Black compared with White adults with or without stroke, with no statistically significant differences after multivariable adjustment.

Racial Disparities in Arterial Stiffness Between Healthy Whites and African Americans in the United States: A Meta-analysis.

BACKGROUND: African Americans (AAs) present with cardiovascular disease (CVD) risk factors at younger ages than whites. Consequently, CVD and stroke occur at a higher incidence and at earlier decades in life in AA populations. Arterial stiffness is a predictor of CVD outcomes and partially explains the CVD risk experienced by racial minorities. We evaluated the differences in arterial stiffness observed in AAs and whites through a systematic review and meta-analysis. METHODS: We searched PubMed and SCOPUS for comparative studies published March 1995 to November 29, 2017 comparing arterial stiffness assessments (pulse wave velocity, augmentation index, and central blood pressure) between AAs and whites. Two independent reviewers examined 195 titles/abstracts, 85 full text articles and 11 articles were included in the meta-analysis using random effects modeling approaches. MAIN RESULTS: A total of 5060 white and 3225 AAs were included across 11 relevant studies. Carotid-femoral pulse wave velocity (cfPWV) measures were statistically different between AAs and whites (mean difference = -0.44, 95% confidence interval [CI]: -[-0.67, -0.21], p = 0.0002). Aortic femoral pulse wave velocity was significantly different between AAs and whites (mean difference = -0.21, [95% CI] -0.35, -0.07, p = 0.003) regardless of sex. Augmentation index (AIx) and Augmentation index at a 75 beats per minutes heart rate (AIx @75) was also significantly different between AA and whites (mean difference = -4.36 [95% CI] = -6.59, -2,12, p = 0.0001 and -6.26, [95% CI] = -9.19, -3.33, p < 0.0001, respectively). CONCLUSIONS: Racial disparities in arterial stiffness persist among African American racial groups in the United States. The lack of homogeneity in studies capturing racial disparities in cfPWV suggest that additional studies are needed to understand the magnitude of racial differences in African Americans and whites that might be clinically relevant.

A Stromal Cell-Derived Factor 1α Analogue Improves Endothelial Cell Function in Lipopolysaccharide-Induced Acute Respiratory Distress Syndrome.

Endothelial cell (EC) dysfunction is a critical mediator of the acute respiratory distress syndrome (ARDS). Recent studies have demonstrated that stromal cell-derived factor 1α (SDF-1α) promotes EC barrier integrity. Our previous studies used a SDF-1α analogue CTCE-0214 (CTCE) in experimental sepsis and demonstrated that it attenuated vascular leak and modulated microRNA (miR) levels. We examined the hypothesis that CTCE improves EC function in lipopolysaccharide (LPS)-induced ARDS through increasing miR-126 expression. Human microvascular endothelial cells (HMVECs) were treated with thrombin to disrupt the EC integrity followed by incubation with CTCE or SDF-1α. Barrier function was determined by trans-endothelial electrical resistance assay. CTCE-induced alterations in miRNA expression and signaling pathways involved in barrier function were determined. Thrombin-induced vascular leak was abrogated by both CTCE and SDF-1α. CTCE also prevented thrombin-induced decreases of vascular endothelial (VE)-cadherin cell surface expression and expansion of the intercellular space. CTCE increased miR-126 levels and induced activation of AKT/Rac 1 signaling. Cotreatment with a miR-126 inhibitor blocked the protective effects of CTCE on AKT activation and endothelial permeability. In subsequent in vivo studies, ARDS was induced by intratracheal instillation of LPS. Intravenous injection of CTCE diminished the injury severity as evidenced by significant reductions in protein, immune cells, inflammatory cytokines and chemokines in the bronchoalveolar lavage fluid, increased miR-126 expression and decreased pulmonary vascular leak and alveolar edema. Taken together, our data show that CTCE improves endothelial barrier integrity through increased expression of miR-126 and activation of Rac 1 signaling and represents an important potential therapeutic strategy in ARDS.

High tech and high touch: Recruitment strategies for enrolling African American stroke survivors in Community Based Intervention under Nurse Guidance after stroke (CINGS) trial.

BACKGROUND: Substantial effort has been undertaken to improve the recruitment and retention of participants in stroke trials. African Americans are disproportionately under-represented in stroke clinical trials as well as clinical trials for other chronic disease conditions. To circumvent barriers to recruitment, clinical trial recruitment strategies used to recruit African Americans have focused on different aspects of community engagement. PURPOSE: This study examined a community-engaged, multi-phased tailored approach to recruiting African Americans with stroke. The recruitment approach described was designed to support the Community Based Intervention under Nurse Guidance after Stroke (CINGS) trial, part of the Wide Spectrum Investigation of Stroke Outcome Disparities on Multiple Levels (WISSDOM) Center established to explore stroke disparities. METHODS: A multiple-phased recruitment approach was undertaken and involved a recruitment planning phase and a recruitment phase. The recruitment planning phase involved the use of focus groups designed to explore barriers and facilitators of stroke recovery. The active recruitment phase included multiple strategies with ongoing evaluation. RESULTS: Information gained from focus groups offered insights into strategies critical to recruiting African Americans with stroke for behavioral research during the early recovery period. Strategies to enhance the identification of and recruitment of potential participants included use of: a) a hospital system stroke database, b) system-wide friendly visits/warm handoff approaches, c) electronic health record, d) associated external sites and e) protocol adjustments. CONCLUSIONS: Developing tailored approaches to curtail barriers to research participation is critical for increasing the probability of reaching African American study participant recruitment and retention goals. Research teams may require training in community-engagement research strategies essential for obtaining achieving target recruitment goals.

Impact of COVID-19 on Clinical Research and Inclusion of Diverse Populations.

The randomized clinical trial (RCT) has long been recognized as the 'gold standard' for developing evidence for clinical treatments and vaccines; however, the successful implementation and translation of these findings is predicated upon external validity. The generalization of RCT findings are jeopardized by the lack of participation of at-risk groups such as African Americans, with long-recognized disproportional representation. Distinct factors that deter participation in RCTs include distrust, access, recruitment strategies, perceptions of research, and socioeconomic factors. While strategies have been implemented to improve external validity with greater participation among all segments of the population in RCTs, the coronavirus disease 2019 (COVID-19) pandemic may exacerbate disparities in RCT participation with the potential impact of delaying treatment development and vaccine interventions that are applicable and generalizable. Thus, it is essential to include diverse populations in such strategies and RCTs. This Perspective aims to direct attention to the additional harm from the pandemic as well as a refocus on the unresolved lack of inclusion of diverse populations in conducting RCTs.

Racial Disparities in Stroke Recovery Persistence in the Post-Acute Stroke Recovery Phase: Evidence from the Health and Retirement Study.

Background and Purpose: Blacks have a higher burden of post-stroke disability. Factors associated with racial differences in long-term post-stroke disability are not well-understood. Our aim was to assess the long-term racial differences in risk factors associated with stroke recovery. Methods: We examined Health and Retirement Study (HRS) longitudinal interview data collected from adults living with stroke who were aged >50 years during 2000-2014. Analysis of 1,002 first-time, non-Hispanic, Black (210) or White (792) stroke survivors with data on activities of daily living (ADL), fine motor skills (FMS) and gross motor skills (GMS) was conducted. Ordinal regression analysis was used to assess the impact of sex, race, household residents, household income, comorbidities, and the time since having a stroke on functional outcomes. Results: Black stroke survivors were younger compared with Whites (69 ± 10.4 vs 75 ± 11.9). The majority (~65%) of Black stroke survivors were female compared with about 54% White female stroke survivors (P=.007). Black stroke survivors had more household residents (P<.001) and comorbidities (P<.001). Aging, being female, being Black and a longer time since stroke were associated with a higher odds of having increased difficulty in ADL, FMS and/or GMS. Comorbidities were associated with increased difficulty with GMS. Black race increased the impact of comorbidities on ADL and FMS in comparison with Whites. Conclusion: Our data suggest that the effects of aging, sex and unique factors associated with race should be taken into consideration for future studies of post-stroke recovery and therapy.

L-sepiapterin restores SLE serum-induced markers of endothelial function in endothelial cells.

OBJECTIVE: SLE serves as an independent risk factor` for endothelial dysfunction (ED) not explained by Framingham risk factors. We sought to understand the development of SLE-induced ED on a cellular level in order to develop strategies aimed at reversing cellular abnormalities. This study assessed the impact of SLE patient serum on endothelial nitric oxide synthase (eNOS), nitric oxide (NO) production and functional changes in the cell. METHODS: Human umbilical vein endothelial cells (HUVECs) cultured in serum of either SLE (n=25) or healthy patients (n=14) or endothelial basal medium 2 (EBM-2) culture media supplemented with fetal bovine serum with or without L-sepiapterin were used for our studies. We applied the fluorescent probe DAF-FM diacetate for intracellular NO detection using flow cytometry. Total RNA isolates were analysed using reverse transcription PCR for eNOS mRNA expression. Oxygen consumption rate was determined using seahorse analysis. Neutrophil adhesion and migration were determined using a calcein AM microscopy assay. RESULTS: The mRNA expression of eNOS was increased in SLE cultured HUVECs compared with healthy control (p<0.05). The SLE eNOS mRNA level correlated with SLE patient age (p=0.008); however, this trend was not observed with healthy patients. SLE serum reduced NO production in HUVECs compared with EBM-2 cultured cells (p<0.05). Co-treatment of endothelial cells with L-sepiapterin preserved HUVEC capacity to produce NO in SLE conditions (p<0.01). SLE serum enhanced neutrophil migration (p<0.01) but not neutrophil adhesion compared with healthy controls. The bioenergetic health index was not different. CONCLUSIONS: SLE likely causes disruption of endothelial cell eNOS function and NO modulated pathways.

Racial and ethnic disparities in stroke outcomes: a scoping review of post-stroke disability assessment tools.

Purpose: To identify how post-stroke disability outcomes are assessed in studies that examine racial/ethnic disparities and to map the identified assessment content to the International Classification of Functioning, Disability, and Health (ICF) across the time course of stroke recovery. Methods: We conducted a scoping review of the literature. Articles published between January 2001 and July 2017 were identified through Scopus, PubMed, CINAHL, and PsycINFO according to predefined inclusion and exclusion criteria. Results: We identified 1791 articles through database and hand-searching strategies. Of the articles, 194 met inclusion criteria for full-text review, and 41 met inclusion criteria for study inclusion. The included studies used a variety of outcome measures encompassing domains within the ICF: body functions, activities, participation, and contextual factors across the time course of stroke recovery. We discovered disproportionate representation among racial/ethnic groups in the post-stroke disability disparities literature. Conclusions: A wide variety of assessments are used to examine disparities in post-stroke disability across the time course of stroke recovery. Several studies have identified disparities through a variety of assessments; however, substantial problems abound from the assessments used including inconsistent use of assessments, lacking evidence on the validity of assessments among racial/ethnic groups, and inadequate representation among all racial/ethnic populations comprising the US. Implications for Rehabilitation An enhanced understanding of racial/ethnic disparities in post-stroke disability outcomes is inherently important among rehabilitation practitioners who frequently engage with racial/ethnic minority populations across the time course of stroke recovery. Clinicians should carefully consider the psychometric properties of assessment tools to counter potential racial bias. Clinicians should be aware that many assessments used in stroke rehabilitation lack cultural sensitivity and could result in inaccurate assessment findings.

Differences in plasma levels of long chain and very long chain ceramides between African Americans and whites: An observational study.

BACKGROUND: Population-wide reductions in cardiovascular disease (CVD) have not been equally shared in the African American community due to a higher burden of CVD risk factors such as metabolic disorders and obesity. Differential concentrations of sphingolipids such as ceramide, sphingosine, and sphingosine 1-phosphate (S1P) has been associated with the development of CVD, metabolic disorders (MetD), and obesity. Whether African Americans have disparate expression levels of sphingolipids that explain higher burdens of CVD remains unknown. METHODS: A cross sectional analysis of plasma concentrations of ceramides, sphingosine, and S1P were measured from 8 whites and 7 African Americans without metabolic disorders and 7 whites and 8 African Americans with metabolic disorders using high performance liquid chromatography/tandem mass spectrometry methodology (HPLC/MS-MS). Subjects were stratified by both race and metabolic status. Subjects with one or more of the following physician confirmed diagnosis: diabetes, hypertension, hypercholesterolemia, or dyslipidemia were classified as having metabolic disease (MetD). Data was analyzed using a Two-Way ANOVA and Tukey's post hoc test. RESULTS: Total ceramide levels were increased in African Americans compared to African Americans with MetD. Ceramide C16 levels were higher in whites with MetD compared to African Americans with MetD (p<0.05). Ceramide C20 levels were higher in whites with MetD compared to whites. Ceramide C20 levels were higher in African Americans compared to African Americans with MetD. Furthermore, whites with MetD had higher levels of C20 compared to African Americans with MetD (p<0.0001). Ceramide C24:0 and C24:1 in African Americans was higher compared to African Americans with MetD (p<0.05). The plasma concentration of Sph-1P ceramide was higher in African Americans vs whites (p = 0.01). Lastly, ceramide C20 negatively correlated with hemoglobin A1c (HbA1c) levels in our study cohort. CONCLUSIONS: Plasma ceramide concentration patterns are distinct in African Americans with MetD. Further research with larger samples sizes are needed to confirm these findings and to understand whether racial disparities in sphingolipid concentrations have potential therapeutic implications for CVD-related health outcomes.

Application of Deacetylated Poly-N-Acetyl Glucosamine Nanoparticles for the Delivery of miR-126 for the Treatment of Cecal Ligation and Puncture-Induced Sepsis.

Sepsis is an acute inflammatory syndrome in response to infection. In some cases, excessive inflammation from sepsis results in endothelial dysfunction and subsequent increased vascular permeability leading to organ failure. We previously showed that treatment with endothelial progenitor cells, which highly express microRNA-126 (miR-126), improved survival in mice subjected to cecal ligation and puncture (CLP) sepsis. miRNAs are important regulators of gene expression and cell function, play a major role in endothelial homeostasis, and may represent an emerging therapeutic modality. However, delivery of miRNAs to cells in vitro and in vivo is challenging due to rapid degradation by ubiquitous RNases. Herein, we developed a nanoparticle delivery system separately combining deacetylated poly-N-acetyl glucosamine (DEAC-pGlcNAc) polymers with miRNA-126-3p and miRNA-126-5p and testing these combinations in vitro and in vivo. Our results demonstrate that DEAC-pGlcNAc polymers have an appropriate size and zeta potential for cellular uptake and when complexed, DEAC-pGlcNAc protects miRNA from RNase A degradation. Further, DEAC-pGlcNAc efficiently encapsulates miRNAs as evidenced by preventing their migration in an agarose gel. The DEAC-pGlcNAc-miRNA complexes were taken up by multiple cell types and the delivered miRNAs had biological effects on their targets in vitro including pERK and DLK-1. In addition, we found that delivery of DEAC-pGlcNAc alone or DEAC-pGlcNAc:miRNA-126-5p nanoparticles to septic animals significantly improved survival, preserved vascular integrity, and modulated cytokine production. These composite studies support the concept that DEAC-pGlcNAc nanoparticles are an effective platform for delivering miRNAs and that they may provide therapeutic benefit in sepsis.

The role of miRNAs in cardiovascular disease risk factors.

Coronary artery disease and atherosclerosis are complex pathologies that develop over time due to genetic and environmental factors. Differential expression of miRNAs has been identified in patients with coronary artery disease and atherosclerosis, however, their association with cardiovascular disease risk factors, including hyperlipidemia, hypertension, obesity, diabetes, lack of physical activity and smoking, remains unclear. This review examines the role of miRNAs as either biomarkers or potential contributors to the pathophysiology of these aforementioned risk factors. It is intended to provide an overview of the published literature which describes alterations in miRNA levels in both human and animal studies of cardiovascular risk factors and when known, the possible mechanism by which these miRNAs may exert either beneficial or deleterious effects. The intent of this review is engage clinical, translational, and basic scientists to design future collaborative studies to further elucidate the potential role of miRNAs in cardiovascular diseases.

Role of interferon alpha in endothelial dysfunction: insights into endothelial nitric oxide synthase-related mechanisms.

Systemic lupus erythematosus (SLE) is an autoimmune disease that is characterized by the production of autoantibodies against nuclear antigens such as double-stranded DNA. Lupus predominantly affects women (ratio, 9:1). Moreover, premenopausal women with SLE are 50 times more likely to have a myocardial infarction. Although specific risk factors for advanced cardiovascular complications have not been identified in this patient population, endothelial dysfunction is highly prevalent. Recent studies show that the type I interferon signature gene expression coincides with impaired brachial artery flow-mediated dilation and diminished endothelial progenitor cell circulation, both markers of impaired endothelial function. Although many factors promote the development of vascular endothelial dysfunction, all pathways converge on the diminished activity of endothelial nitric oxide synthase (eNOS) and loss of nitric oxide (NO) bioavailability. Studies examining the effects of type I interferons on eNOS and NO in SLE are missing. This literature review examines the current literature regarding the role of type I interferons in cardiovascular disease and its known effects on regulators of eNOS and NO bioavailability that are important for proper endothelial cell function.

A critical role of the transcription factor fli-1 in murine lupus development by regulation of interleukin-6 expression.

OBJECTIVE: The Fli-1 transcription factor is implicated in the pathogenesis of systemic lupus erythematosus (SLE), both in humans and in animal models. Dysregulation of interleukin-6 (IL-6) is also associated with SLE. The purpose of this study was to investigate whether Fli-1 directly regulates the expression of IL-6. METHODS: Sera were collected from wild-type and Fli-1-heterozygous (Fli-1(+/-) ) MRL/lpr mice, and the concentration of IL-6 was measured by enzyme-linked immunosorbent assay (ELISA). Expression of IL-6 in the kidney was measured by real-time polymerase chain reaction analysis. T cells were isolated from wild-type and Fli-1(+/-) MRL/lpr mice and stimulated with CD3/CD28 beads, and the concentration of IL-6 in the supernatants was measured by ELISA. MS1 endothelial cells were transfected with Fli-1 and control small interfering RNA, and the production of IL-6 was compared after lipopolysaccharide stimulation. A chromatin immunoprecipitation (ChIP) assay was performed to determine whether Fli-1 binds to the IL-6 promoter region. Transient transfections with the NIH3T3 cell line were performed to examine whether Fli-1 regulates the expression of IL-6. RESULTS: Fli-1(+/-) MRL/lpr mice had significantly decreased IL-6 levels in sera and reduced expression of IL-6 in kidneys as compared to their wild-type littermates. T cells isolated from Fli-1(+/-) MRL/lpr mice produced less IL-6 than did those from wild-type mice. Inhibiting the expression of Fli-1 in endothelial cells resulted in reduced production of IL-6. The ChIP assay revealed direct binding of Fli-1 to 3 regions within the IL-6 promoter. Fli-1 activated transcription from the IL-6 promoter in a dose-dependent manner. CONCLUSION: The direct regulation of IL-6 expression by Fli-1 represents one possible mechanism for the protective effect of decreased Fli-1 expression in lupus.