The pathophysiology of cachexia is multifactorial and involves complex interactions between pro-inflammatory cytokines, neurohormonal changes, and metabolic abnormalities. Key factors include:
1. Pro-inflammatory Cytokines: Elevated levels of cytokines such as TNF-alpha, IL-6, and IL-1 are commonly observed. These cytokines promote muscle wasting by enhancing protein degradation pathways. 2. Hormonal Imbalance: Changes in hormones such as leptin, ghrelin, and insulin can also contribute to cachexia. For example, resistance to anabolic hormones like insulin and IGF-1 exacerbates muscle loss. 3. Metabolic Changes: Increased energy expenditure and altered substrate metabolism are hallmarks of cachexia. There is often an increased rate of gluconeogenesis and lipid mobilization.
