Activity level, apoptosis, and development of cachexia in Apc(Min/+) mice

Area of Science:

• Animal models of disease
• Cancer cachexia research
• Muscle physiology

Background:

• Cachexia diagnosis involves unintentional weight loss, fatigue, anorexia, and low muscle mass.
• Systemic inflammation, metabolic changes, and anemia characterize cachexia.
• Apc(Min/+) mice model cachexia linked to intestinal tumors, inflammation, and elevated IL-6.

Purpose of the Study:

• To investigate the temporal relationship between physical activity, anemia, muscle apoptosis, and mass loss in cachexia.
• To analyze changes in voluntary wheel running performance in Apc(Min/+) mice during cachexia development.

Main Methods:

• Apc(Min/+) mice were divided into voluntary wheel running and sedentary groups.
• Mice were monitored from 5 to 26 weeks of age.
• Cachectic symptoms, anemia, muscle apoptosis markers (BAX), and hemoglobin levels were assessed.

Main Results:

• Decreased wheel running performance was observed at 15 weeks in severely cachectic mice.
• Anemia and body weight loss appeared later, around 18 weeks.
• Severely cachectic mice showed lower hemoglobin and increased BAX protein in muscles compared to mildly cachectic mice.

Conclusions:

• Reduced physical activity precedes significant body mass loss and anemia in this cachexia model.
• Muscle apoptosis is elevated in severe cachexia, affecting both red and white muscle fibers.
• Inherent muscle oxidative capacity does not prevent muscle apoptosis in cachexia.