Study neutrophils important for self-healing after a heart attack

Healing process after a heart attack significantly influenced by neutrophils
In a heart attack, numerous heart muscle cells die within a short time and not infrequently a heart attack is fatal. Survival of those affected, forming an inflammation in the affected tissue, which is triggered by neutrophils, explains the Ludwig Maximilian University of Munich (LMU). A recent study by the research team led by Professor Sabine Steffens from the Institute of Epidemiology and Prophylaxis of Circulatory Diseases at the LMU Hospital has now shown that neutrophils are also crucial in stopping the inflammation.

The inflammation caused by neutrophils after a heart attack is crucial for the healing process, according to the researchers. But excessive inflammation also has harmful consequences. However, according to the researchers, neutrophils are also involved in stopping the inflammatory process. The results of their study have been published by Prof. Steffens and colleagues in the journal "European Heart Journal".

The self-healing after a heart attack is mainly controlled by neutrophil granulocytes. (Image: igor / fotolia.com)

Inflammation with positive and negative consequences
Previous studies have already shown that neutrophils (neutrophils, for short) trigger inflammation in the affected tissue after a heart attack. The immune system reacts with inflammation to the large number of dead heart muscle cells. "Neutrophils migrate into the damaged heart muscle immediately after an infarction. They can release various substances that can render pathogens harmless and trigger an acute inflammatory reaction, "says the LMU. As a result, after a heart attack, the healing process is triggered, in which the dead tissue is degraded. In the end, however, the inflammation causes scars to form and the heart muscle to expand, explain the researchers. The result is often a heart failure, which requires a permanent aftercare.

Neutrophils start and stop the inflammation
According to the LMU, the working group of Sabine Steffens was able to prove "for the first time in a mouse model that neutrophils are not only the cause of inflammation but also crucial for infarct healing." They release substances that favor the development of certain monocytes, the in turn, drive the repair process. According to Professor Sabine Steffens, the "inflammation is not necessarily just harmful, but even necessary for the process of orderly wound healing in moderation." So far, the positive role of the neutrophils have been overlooked. The current study shows that neutrophils are also crucial in that the inflammation dissolves again and the tissue can stabilize. "Our result is surprising in that so far the neutrophils have only been classified as having a harmful effect following an acute myocardial infarction," says the Professor of Clinical Pathobiochemistry.

New treatment approaches possible
Based on the new results, it becomes clear that the function of the neutrophils is not fully understood, the researchers concluded. This also has implications for current therapeutic approaches that rely on a reduction in the number of neutrophils following a heart attack to control the inflammatory process. "It depends on the right balance. There could be a limit from which the positive effect of neutrophils tilts, "emphasizes Prof. Steffens. Too much neutrophil reduction, according to the expert, could cause the healing process to be impaired. Instead, it may be a promising approach instead to strengthen the development of those monocytes that accelerate the repair process. Further studies now need to uncover the signaling pathways and regulatory processes leading to their formation. (Fp)