PPARalpha activator effects on Ang II-induced vascular oxidative stress and inflammation

Docosahexaenoic acid (DHA), a peroxisome proliferator–activated receptor-α (PPARα) activator, reduces blood pressure (BP) in some hypertensive models by unclear mechanisms. We tested the hypothesis that DHA would prevent BP elevation and improve vascular dysfunction in angiotensin (Ang) II–infused rats by modulating of NADPH oxidase activity and inflammation in vascular wall. Sprague-Dawley rats received Ang II (120 ng/kg per minute SC) with or without DHA (2.5 mL of oil containing 40% DHA/d PO) for 7 days. Systolic BP (mm Hg), elevated in Ang II–infused rats (172±3) versus controls (108±2, P<0.01), was reduced by DHA (112±4). In mesenteric small arteries studied in a pressurized myograph, media/lumen ratio was increased (P<0.05) and acetylcholine-induced relaxation impaired in Ang II–infused rats (P<0.05); both were normalized by DHA. In blood vessels of Ang II–infused rats, NADPH oxidase activity measured by chemiluminescence and expression of adhesion molecules intercellular adhesion molecule and vascular cell adhesion molecule-1 were significantly increased. These changes were abrogated by DHA. PPARα activator DHA attenuated the development of hypertension, corrected structural abnormalities, and improved endothelial dysfunction induced by Ang II. These effects are associated with decreased oxidative stress and inflammation in the vascular wall

Angiotensin receptor blocker added to previous antihypertensive agents on arteries of diabetic hypertensive patients

Lowering elevated blood pressure (BP) in diabetic hypertensive individuals decreases cardiovascular events. We questioned whether remodeling of resistance arteries from hypertensive diabetic patients would improve after 1 year of tight BP control with addition of either the angiotensin receptor blocker (ARB) valsartan or the β-blocker (BB) atenolol to previous therapy, which included angiotensin-converting enzyme inhibitors (ACEIs) and/or calcium channel blockers. Twenty-eight hypertensive type 2 diabetic patients treated with oral hypoglycemic and antihypertensive agents (not receiving ARBs or BBs) were randomly assigned to double-blind treatment for 1 year with valsartan (80 to 160 mg) or atenolol (50 to 100 mg) daily, added to previous therapy. Resistance arteries dissected from gluteal subcutaneous tissues were assessed on a pressurized myograph. After 1 year of treatment, systolic and diastolic BP and glycemia were equally well controlled in the valsartan and atenolol groups. Endothelium-dependent and independent relaxation did not change in the treated groups. After 1 year of treatment, resistance artery media:lumen ratio decreased in the valsartan group (7.9±0.5% after versus 9.8±0.6% before; P<0.05) but not in the atenolol-treated group (9.9±0.9% versus 10.6±1%; P value not significant). Artery walls from atenolol-treated patients became stiffer, with no change in the valsartan-treated patients. In conclusion, similar intensive BP control for 1 year with valsartan was associated with improved structure of resistance arteries in diabetic hypertensive patients, whereas vessels from atenolol-treated patients exhibited unchanged remodeling and a stiffer wall. The addition of ARBs but not BBs to antihypertensive medications that may include angiotensin-converting enzyme inhibitors and/or calcium channel blockers results in an improvement in resistance artery remodeling in diabetic hypertensive patients

ETA receptor mediates altered leukocyte-endothelial cell interaction and adhesion molecules expression in DOCA-salt rats

Leukocyte adhesion to endothelial cells plays a key role in inflammatory processes associated with end-organ injury. Endothelin-1 (ET-1), which stimulates inflammatory processes, contributes to cardiovascular damage in deoxycorticosterone (DOCA)–salt hypertension. We investigated whether ETA receptor blockade modulates in vivo leukocyte–endothelial cell interactions and expression of cell adhesion molecules (CAM) involved in these processes. DOCA–salt and control uninephrectomized rats were treated with the ETA antagonist BMS182874 (40 mg/kg per day) or vehicle. Analysis of CAMs expression by reverse transcription-polymerase chain reaction and immunohistochemistry showed increased cardiac platelet selectin (P-selectin), detected mainly in endothelial cells, and vascular cell adhesion molecule-1 (VCAM-1), but not intercellular adhesion molecule-1 (ICAM-1), in DOCA–salt rats. Cardiac expression of endothelial selectin (E-selectin) was decreased, whereas immunoreactivity to ED-1 and myeloperoxidase (MPO) activity, markers of macrophage and leukocyte infiltration, respectively, were increased in DOCA-salt. Leukocyte–endothelial cell interaction, functionally assessed in venules of internal spermatic fascia by intravital microscopy, was significantly altered in DOCA–salt rats as evidenced by increased leukocyte adhesion and decreased rolling. BMS182874 treatment normalized leukocyte–endothelium interactions, decreased cardiac VCAM-1 expression in DOCA and control groups, and had no effects on ICAM-1 expression. BMS182874 also increased E-selectin and abolished P-selectin expression in DOCA-salt, but not in control rats. The ETA antagonist reduced cardiac ED-1 content and MPO activity and prevented cardiac damage in DOCA–salt rats. These data indicate that ET-1 participates, via activation of ETA receptors, in altered leukocyte–endothelial cell interactions in DOCA–salt rats, possibly by modulating expression of CAMs, and that the inflammatory status is associated with cardiac damage in mineralocorticoid hypertension

Textual politics of Alabama\u27s historical markers: Slavery, emancipation, and civil rights

In light of recent protests and debates over Confederate symbols, markers, and flags after the 2015 Charleston shooting, the South remains fertile ground for critically reflecting on the role of history in shaping the present. State historical marker programs are a near ubiquitous feature of the United States\u27 commemorative landscape, used to retell history at important sites. However, geographers and other memory studies scholars have not devoted much time or effort in researching historical markers, in part because they are often considered mundane or they are ignored in favor of researching stand-alone monuments or other memory projects. Engaging with textual politics-the belief that language, words, and narrative are politically active within commemorative landscapes-along with the concepts of historical responsibility and surrogation, this chapter presents an analysis of the Alabama Historical Association\u27s marker program and its presentation and interpretation of African-American history. Findings include that historical periods of slavery and emancipation have largely been ignored, while the Civil Rights Movement is more widely represented and celebrated as a success story

The significance of micro- and macrovascular biomarkers on cardiovascular outcome in chronic kidney disease: a prospective cohort study

Measures of small and large artery dysfunction have not been investigated in a single cohort for the prediction of cardiovascular (CV) events in patients with nondialysed (ND) chronic kidney disease (CKD). This prospective cohort study aimed to determine whether central pulse wave velocity (cPWV), central pulse pressure (CPP) or microvascular post-occlusive reactive hyperaemia area (PORHHA) independently predict CV events and mortality in CKD-ND. A total of 94 stage 1-5 CKD-ND (65.3[plusmn]13.1 years; estimated glomerular filtration rate 35.3 (22.8-49.4) ml[thinsp]min-1 per 1.73[thinsp]m2) patients were followed-up for a median of 52 (36-65) months and had baseline cPWV and CPP measured by applanation tonometry and PORHHA by laser Doppler flowmetry. Multiple failure time Cox regression models were used to determine the predictive role of vascular parameters on CV mortality and events. Based on multiple linear regressions, baseline age, diabetes, CV disease, and systolic blood pressure (SBP) were independently related to cPWV (R2=0.3), SBP and PORHHA to CPP (R2=0.45), whereas CPP was the only parameter independently related to PORHHA (R2=0.16, all P<0.05). During follow-up, 41 CV events occurred (14 CV deaths). In univariate analyses, cPWV (1.07 (1.02-1.13) per m[thinsp]s-1), CPP (1.04 (1.01-1.07) per mm[thinsp]Hg) and lnPORHHA (0.70 (0.58-0.85) per ln(PU [times] s)) were all related to the outcome. Baseline diabetes (HR 3.07 (1.65-5.68)), lnFGF23 (fibroblast growth factor-23; 1.86 (1.13-3.06) per RU[thinsp]ml-1) and CPP (1.04 (1.01-1.07) per mm[thinsp]Hg) were independent predictors of CV events. The impaired pulsatile component of large arteries (CPP) independently of other vascular markers (cPWV, PORHHA) predicted CV outcomes in CKD-ND. CPP may integrate the information provided by cPWV and PORHHA