Blood pressure and TNF-α act synergistically to increase leucocyte CD11b adhesion molecule expression in the BELFAST study: implications for better blood pressure control in ageing

Abstract

Hypertension, a key risk factor for stroke, cardiovascular disease and dementia, is associated with chronic vascular inflammation, and although poorly understood, putative mechanisms include pro-inflammatory responses induced by mechanical stretching, with cytokine release and associated up-regulated expression of adhesion molecules. Because blood pressure increases with age, we measured baseline and tumour necrosis alpha (TNF-α)-stimulated CD11b/CD18 adhesion molecule expression on leucocytes to assess any association between the two. In 38 subjects (mean age 85 years), consecutively enrolled from Belfast Elderly Longitudinal Free-Living Aging Study (BELFAST), baseline and TNF-α-stimulated CD11b/CD18 expression on separated monocytes and neutrophils increased with systolic blood pressure >120 mmHg (p = 0.05) and for lymphocytes, with diastolic blood pressure >80 mmHg (p < 0.05).These findings show increased potential stickiness of intravascular cells with increasing blood pressure which is accentuated by TNF-α, and suggest mechanistic reasons why better hypertension control is important.

d(−) Lactic Acid-Induced Adhesion of Bovine Neutrophils onto Endothelial Cells Is Dependent on Neutrophils Extracellular Traps Formation and CD11b Expression

“…Bovine neutrophils treated with Ar-c155858 to inhibit MCT1 significantly decreased neutrophil adhesion of cells that were previously exposed to 2 and 5 mM d (−) lactic acid (Figure 4 C). TNFα is a pro-inflammatory cytokine that has been shown to stimulate adhesion of neutrophils to endothelium through activation of the β-integrin, CD11b/CD18 ( 61 ), and NET formation ( 15 ). TNFα-induced effects on neutrophils are thought to be mediated through activation of TNF receptors ( 62 ) and not through MCT transporter mechanisms.…”

Basal neutrophil function in human aging: Implications in endothelial cell adhesion

“…In a cohort study with healthy aged individuals, no differences in neutrophil CD11b expression were found when compared to young subjects (Butcher et al, ). Interestingly, increased CD11b levels have been associated with hypertension, a condition of high prevalence in the elderly population (Rea et al, ). Also, a study conducted with postmenopausal women showed a strong positive correlation of carotid intima‐media thickness with CD11b expression and membrane‐bound TNF‐α (Figueroa‐Vega et al, ), strengthening the connection between CD11b levels and pro‐inflammatory parameters, leading to cardiovascular risk factors.…”