Morphometric Changes of the Myenteric Plexus in the Colon of the Mice-D-Galactose Ageing Model

Abstract

Ageing-related diseases are paramount for understanding the socioeconomic impact of the postmodern society. Neuronal degeneration is a known phenomenon in ageing. The D-galactose model of accelerated ageing is widely used in age-associated neuronal cell death because of the oxidative stress it induces, which correlates to reduced cognitive performance and robustly detectable neuronal shrinkage in the CNS. This study aims at demonstrating the morphological changes of neurons of the myenteric plexus in mice treated with D-galactose. D-galactose was given orally with drinking water, resulting in an average dose of 500 mg/kg daily for six weeks. In the D-galactose accelerated ageing model, a significant size reduction of the neuronal perikarya of the myenteric plexus was observed all along the large intestine. The average soma area at the caecum in the control group was 305 µm2, which was reduced by almost 20% in the ageing model. In contrast, at the level of the proximal colon in the D-galactose ageing model, the average area of the neuronal soma was 280 µm2, a reduction of 30%. The most significant reduction has been observed at the level of the distal colon, where the neuronal soma was reduced by 40%. There is a significant reduction of the area of the neuronal bodies in the myenteric plexus among different parts of the mice's large intestine in the accelerated ageing model. It can be inferred that D-galactose-induced morphological changes in the myenteric plexus may be related to the increased gastrointestinal motility dysfunction with ageing.