Does Surgical Stress Impair Skeletal Muscle Protein and Carbohydrate Metabolism?

Background: Skeletal muscle wasting or decrease in muscle mass occurs as a result of alteration in the body's mechanisms to make or break muscle protein. In animal models, the pathway termed as 'ubiquitin-proteasome pathway' (UPP) is primarily responsible for the regulation of skeletal muscle protein loss in wasting conditions and during infection(sepsis). Skeletal muscle wasting is noticed in patients having major surgery due to the inflammatory reaction triggered by special group of proteins called cytokines (inflammatory proteins), resulting in reduced muscle strength, impaired capacity to fight infections, change in bowel function, increased clinical complications and prolonged recovery. Major surgery also leads to decreased sensitivity to hormone known as insulin, resulting in 'diabeteslike'state.

We hypothesize that susceptibility of patients undergoing major abdominal surgery, to skeletal muscle wasting and insulin resistance, is determined by stress response to surgery over time, leading to changes in the pathways that make or break muscle protein, namely the Akt/Foxo signalling and UPP. Therefore, the aim of this study is to establish the underlying mechanisms of skeletal muscle wasting and insulin resistance in patients undergoing major abdominal surgery.