Age-Related Changes in the Function and Structure of the Peripheral Sensory Pathway in Mice

• Published in: Neurobiology of aging 2016-09, Vol.45, p.136-148
• Main Authors: Canta, A, Chiorazzi, A, Carozzi, V, Meregalli, C, Oggioni, N, Bossi, M, Rodriguez-Menendez, V, Avezza, F, Crippa, L, Lombardi, R, de Vito, G, Piazza, V, Cavaletti, G, Marmiroli, P
• Format: Article
• Language: English
• Subjects: Aging; Aging - pathology; Aging - physiology; Animals; Female; Ganglia, Spinal - pathology; Ganglia, Spinal - physiology; Ganglia, Spinal - physiopathology; Internal Medicine; Mice; Mice, Inbred C57BL; Morphometric analysis; Nerve conduction velocity; Neural Conduction - physiology; Neural Pathways - pathology; Neural Pathways - physiology; Neural Pathways - physiopathology; Neurology; Peripheral nervous system; Peripheral Nervous System - pathology; Peripheral Nervous System - physiology; Peripheral Nervous System - physiopathology; RP-CARS; Skin - innervation
• ISSN: 0197-4580; 1558-1497
• DOI: 10.1016/j.neurobiolaging.2016.05.014

Abstract This study is aimed at describing the changes occurring in the entire peripheral nervous system (PNS) sensory pathway along a 2-year observation period in a cohort of C57BL/6 mice. The neurophysiological studies evidenced significant differences in the selected time points corresponding to childhood, young adulthood, adulthood and aging (i.e. 1, 7, 15 and 25 month of age), with a parabolic course as function of time. The pathological assessment allowed to demonstrate signs of age-related changes since the age of 7 months, with a remarkable increase in both peripheral nerves and dorsal root ganglia (DRG) at the subsequent time points. These changes were mainly in the myelin sheaths, as also confirmed by the Rotating-Polarization Coherent-Anti-stokes-Raman-scattering (RP-CARS) microscopy analysis. Evident changes were also present at the morphometric analysis performed on the peripheral nerves, DRG neurons and skin biopsies. This extensive, multimodal characterization of the PNS changes in aging provides the background for future mechanistic studies allowing the selection of the most appropriate time points and readouts according to the investigation aims.