A Link Between Mitochondrial Protein Defect and Severe Inflammation

A new study led by Institute for Research in Biomedicine (IRB Barcelona) proposed the concept that inflammation can be caused even by the absence of single protein.

Severe inflammation is the immune response of body involving a vascular system in which plasma and leucocyte movement get increased from blood to injured tissue. It attacks the healthy normal tissue mistaking for the pathogen.

A defect in mitochondria can lead to severe chronic muscle inflammation. In previous studies, the link between a defect in mitochondria and inflammation was known. In a new study,  scientists using mouse model demonstrated that on the removal of single mitochondrial protein can lead to severe chronic muscle inflammation which in turn causes premature death in animals.

The mitochondrial protein opa1 is responsible for fusion of internal membrane fusion in mitochondria is present in muscle and liver and converts food energy into energy for a cell. They are highly dynamic in nature.

During their study, the team examines the mitofusin 1 and 2, opa1 (mitochondrial membrane fusion proteins). In the laboratory, a team of 24 researchers focused their study on the protein opa1 and experimented in mice by removing opa1 protein from their skeletal muscle. They found that they become small and survived only for few months.

They also found that by removing opa1 particularly from skeletal muscle fibres induces a severe inflammatory process and thus inflammation spreads throughout the body. This response causes premature deaths in animals and stops the growth. The scientists also describe the main molecular components of the cell signalling pathway that activates the inflammatory response in muscle.

“This is the first time that we’ve seen that the lack of a muscle mitochondrial protein triggers an inflammatory response of this magnitude, and these observations give us further information on the relation between mitochondria and inflammation,” says Zorzano, author of the study.

The main author of this study said that the results are of biomedical relevance. There are set of diseases called inflammatory myopathies which are a group of disease involving chronic muscle inflammation as well as muscle weakness and pain. According to the author, this result suggests that the cause of inflammatory myopathies can be an alteration in mitochondria and there is much more study needed to be done to find more possible links between the two i.e. inflammation myopathies and mitochondrial defect.