Mitochondrial Energy Shutdown: Uncovering the Link to Inflammation Over Cell Death

Scientists at the University of Freiburg have discovered that mitochondria play a crucial role in cell survival. When energy production in mitochondria stops, a process called apoptosis, or programmed cell death, does not occur. Instead, the cell triggers an inflammatory response. This work was published in the journal Immunity on November 20, 2024.

According to Prof. Dr. Olaf Groß, the study leader, mitochondria help determine whether a cell dies quietly or activates an inflammatory response. He emphasizes that this understanding could lead to new treatments for inflammatory diseases.

Mitochondria produce ATP (adenosine triphosphate), the main energy source for cells. If ATP levels drop sharply, a protein called cytochrome c remains in the mitochondria, preventing apoptosis even when the cell receives death signals. Instead, the mitochondria initiate inflammation, alerting tissue to potential threats.

Researchers found that when mitochondria stop producing energy, a protein sensor known as NLRP3 becomes activated. However, another signal from the cell is needed to fully activate NLRP3. This “two-signal mechanism” ensures that inflammation only occurs under serious threats, protecting healthy cells from unnecessary damage.

These findings could improve treatments for diseases characterized by inflammation, such as gout, type 2 diabetes, and severe COVID-19 cases. Prof. Groß suggests that future drugs might target mitochondria or NLRP3 activation to manage inflammation effectively, helping to protect healthy tissue while enhancing the immune response to infections or cancer.

For more details, see the study by Saller et al. published in Immunity: doi.org/10.1016/j.immuni.2024.10.012.