Dendritic spine changes associated with normal aging

Abstract

Given the rapid rate of population aging and the increased incidence of cognitive decline and neurodegenerative diseases with advanced age, it is important to ascertain the determinants that result in cognitive impairment. It is also important to note that some many of the aged population exhibit ‘successful’ cognitive aging, in which cognitive impairment is minimal. One main goal of normal aging studies is to distinguish the neural changes that occur in unsuccessful (functionally impaired) subjects from those of successful (functionally unimpaired) subjects. In this review, we present some of the structural adaptations that neurons and spines undergo throughout normal aging and discuss their likely contributions to electrophysiological properties and cognition. Structural changes of neurons and dendritic spines during aging, and the functional consequences of such changes, remain poorly understood. Elucidating the structural and functional synaptic age-related changes that lead to cognitive impairment may lead to the development of drug treatments that can restore or protect neural circuits and mediate cognition and successful aging.

Cranial irradiation compromises neuronal architecture in the hippocampus

“…The use of transgenic mice expressing EGFP in specific subsets of neurons greatly facilitates quantitative measurements, thereby obviating the need for more traditional and time-consuming approaches dependent on dye-loading or Golgi-staining of neurons (29). With this system, we have identified neurons within specific hippocampal subfields that satisfy strict morphologic criteria and systematically applied neuron-tracing and spine-analysis algorithms to rigorously characterize the long-term structural plasticity induced by acute radiation exposure.…”

A synopsis on aging—Theories, mechanisms and future prospects

“…Another example is that of the somewhat widespread belief that there is a global neuron loss with age. In fact, the difference in total neuron number over the age range of 20–90 years is less than 10% (Pakkenberg et al, 2003; Pannese, 2011), though some morphological alterations do take place, such as significant decrease loss of synapses (Mostany et al, 2013), axon demyelination (Adamo, 2014) or loss of dendritic spines (Dickstein et al, 2013). …”

Synaptic plasticity at the interface of health and disease: New insights on the role of endoplasmic reticulum intracellular calcium stores

“…This mechanism is known as neural plasticity. It involves a wide range of molecular and cellular processes serving fundamental functions in the central nervous system, such as brain development and circuit formation (Sale et al, 2014;Tottenham, 2014;Vitali and Jabaudon, 2014), learning and memory (Shonesy et al, 2014;Takeuchi et al, 2014;Viola et al, 2014) or aging (Dickstein et al, 2013;van der Zee, 2014).…”