Angiogenesis in old-aged subjects after ischemic stroke: a cautionary note for investigators

Abstract

Angiogenesis represents a form of neovascularisation of exceptional importance in numerous pathological conditions including stroke. In this context it is directly related to neuroregeneration which is seen in close proximity. However, numerous experimental data have been drawn from studies that have ignored the age criterion. This is extremely important as angiogenesis is different in young versus old subjects. Extrapolating data obtained from studies performed in young subjects or "in vitro" to old-age patients could lead to inexact conclusions since the dynamics of angiogenesis is age-dependent.The current review covers the key features of brain senescence including morphological and functional changes related to the brain parenchyma, its vascular network and blood flow which could possibly influence the process of angiogenesis. This is followed by a description of post-stroke angiogenesis and its relationship to neuroregeneration and its modulation by vascular endothelial growth factor (VEGF) and insulin-like growth factor 1 (IGF 1), the most important factors active in old brain after ischemic injury.

Cardiovascular Mortality in Obstructive Sleep Apnea in the Elderly: Role of Long-Term Continuous Positive Airway Pressure Treatment

“…This concurs once again with the findings of two studies that analyzed the Sleep Heart Health Study cohort, which showed an increase in the incidence of new cardiovascular events caused by heart failure in the subgroup of elderly patients with OSA (25) or stroke (median age of stroke patients: 72 years) (27), although cardiovascular mortality was not analyzed in these studies. Although it could be supposed that the 'ischemic preconditioning' hypothesis would endorse protection against intermittent hypoxia in any type of cardiovascular event, most of the data available on this compensatory mechanism derive from studies investigating its effect on coronary circulation (38)(39)(40), and the effect on cerebral circulation is much more open to debate, particularly in the case of elderly people (41)(42)(43). Thus, Wegener et al reported that the protection provided against stroke development by an earlier period of cerebral ischemia (e.g.…”

Vascular remodeling after ischemic stroke: Mechanisms and therapeutic potentials

“…It should be noted that angiogenesis is not always detected in peri-infarct area. Aging is a complex and significant factor that impacts post-ischemic angiogenesis (Petcu et al, 2010). Hypoxia-inducible angiogenesis in rodent hippocampus decreases with aging (Ingraham et al, 2008).…”

Blood−brain barrier breakdown and neovascularization processes after stroke and traumatic brain injury

“…Two key parameters influence restoration of blood flow: presence of collaterals and a capacity to undergo vascular remodeling and produce angiogenic mediators. A majority of the research reveals that spontaneous vascular remodeling occurs after TBI and stroke [71,72 ▪ ,73] with exceptions that show the absence of vascular remodeling depending upon the region of assessment [74], impaired plasticity and remodeling associated with age [75–77] and comorbid conditions [78,79]. Vascular modeling is associated with improved neurological outcomes [73].…”