Mitochondrial DNA Carried in Blood Can Trigger Inflammation

People with sickle cell anaemia have higher levels of Mitochondrial DNA. This DNA is specific to mitochondria which is the cell’s powerhouses circulating in the blood than healthy individuals, likely due to the abnormal retention of mitochondria in red blood cells. The study is Circulating Mitochondrial DNA is a pro-inflammatory DAMP in sickle cell disease was published in the journal Bloo

patients Mitochondrial DNA was found to have fewer chemical modifications relative to healthy people and to trigger the formation of immune-related traps that promote inflammation. Swee Lay Thein, MD, the study’s senior author, said in a press release said that the study findings suggest that measuring DNA of mitochondrial origin could help us better understand its role in pain crises, destruction of red blood cells, and other inflammatory events in sickle cell disease.

Sickle cell anemia is the most common and most severe form of sickle cell disease. It is characterized by the sickling of red blood cells, their distortion into a sickle, rigid shape that is less effective at carrying oxygen throughout the body and the production of inflammatory molecules. This perpetuates a chronic inflammatory state that impairs blood flow and oxygen delivery, leads to organ and tissue damage, and promotes pain crises, or episodes of sudden and severe pain.

A team of researchers at the NHLBI and the NIH have now discovered that mitochondrial abnormalities in red blood cells may contribute to chronic inflammation in SCD. The team first analyzed the DNA extracted from the liquid part of the blood of 34 people with sickle cell anemia and eight healthy volunteers, all participating in one of three ongoing, observational clinical trials.

They found that SCD patients had higher levels of circulating, cell-free Mitochondrial DNA than healthy individuals. Circulating Mitochondrial DNA is composed of DNA fragments generated mainly from mitochondrial damage or general cellular stress.Free-floating from Sickle cell anemia patients also had significantly fewer methyl groups than healthy people. Methyl groups are chemical modifications that are known to regulate gene activity without modifying their underlying genetic sequence.