Effect of oxidative stress on afferent nerve activity from small intestine and colon in young and aged mouse

This thesis addressed the sensory functions of the gastrointestinal (GI) tract with a focus on the effect of oxidative stress on afferent nerve activity from small intestine and colon in young and aged mouse.
Oxidative stress appears to be involved in the pathogenesis of many gastrointestinal conditions, such as inflammatory bowel disease (IBD), colon cancer, and may contribute to the gut dysfunction in ageing. How diverse regions of the gut react to, and handle, elevated levels of ROS in young and aged is unclear. Here, I investigated the effect of oxidative stress on afferent nerve activity in young and aged mice, and if it contributes to age associated changes.
The study used in vitro afferent nerve recordings from jejunum and colon of male mice and concluded that colonic sensory neurons are more sensitive to oxidative stress than jejunum sensory neurons. In the aged group, decreased afferent mechanosensitivity associated with a greater oxidative status was observed only in the aged colonic mucosa. Findings obtained by RNA microarray analysis suggested that the difference between the mouse jejunum and colon in ROS production genes and secondary antioxidant genes may have contributed to the colonic afferent being more sensitive to oxidative stress. In addition, upregulation of inflammatory related genes associated with long-life exposure to high endogenous ROS level are possible factors for colon being more inclined to develop diseases or decreased function as a result of normal ageing.