Inflammation is Beneficial after Acute Muscle Injury
After a muscle injury, you may want to allow some of the inflammation to stay around for a while if you want to encourage healing. That’s the finding of new research published in the FASEB Journal, which found that inflammation helps to heal damaged muscle tissues.
Some inflammation but not a lot helps to heal injured tissue
The mantra for dealing with many muscle injuries is often RICE: rest, ice, compression, and elevation. Individuals are usually advised to begin this treatment immediately after experiencing a soft tissue injury such as a strain, contusion, or sprain, and even more serious injuries until more focused action can be taken. RICE is designed to help reduce inflammation and pain.
Lan Zhou, MD, PhD, at the Neuroinflammation Research Center, Department of Neurosciences, Lerner Research Institute at the Cleveland Clinic in Ohio and his team found that inflammatory cells called macrophages present in acute muscle injury produce high levels of insulin-like growth factor-1 (IGF-1), a substance that increases the rate of muscle repair. Thus inflammation is beneficial when it comes to healing muscle injuries.
Acute inflammation is a defense mechanism that serves a critical purpose: to localize and remove the damaged tissue so the body can begin to heal. This process involves changes in blood flow, the transport of substances such as proteins, fluids, and white blood cells to the injured area, and an increase in the permeability of blood vessels. Thus healing and inflammation go hand in hand.
The researchers made their discovery by studying two groups of mice. One group was genetically modified so they could not produce a healing response to acute muscle injury, while the second group was normal. When mice in both groups were subjected to muscle injury, the animals in the modified group did not heal, but those in the second group did. The investigators discovered that the macrophages present in the injured muscles in the second group of mice produced high amounts of IGF-1, while this response did not occur in the modified mice.
This finding led Gerald Weissmann, MD, editor-in-chief of The FASEB Journal, to note that “For wounds to heal we need controlled inflammation, not too much, and not too little.” He went on to point out that “this study goes a long way to telling us why: insulin-like growth factor and other materials released by inflammatory cells help wounds to heal.” More research in this area is needed, and it could result in new ways to treat acute muscle injuries, including sports injuries.
The FASEB Journal
Updated September 12, 2015