Various researchers have been reporting findings of autoimmune activity in people with autism for some time (the details of that will be another post). Today I came across the newest study to report such findings and was so intrigued that I had to post about it right away. The study is called "Mitochondrial DNA and Anti-mitochondrial Antibodies in Serum of Autistic Children" and was published in the Journal of Neuroinflammation. (It's significant to note that none of the test subjected showed any sign of mitochondrial dysfunction.)
This quote from the abstract sums up the findings of the study:
"We recently showed that the peptide neurotensin (NT) is increased in autistic children. We now show that NT induces release of extracellular mitochondrial DNA (mtDNA) that could act as "autoimmune" trigger. We further show that serum from young autistic patients contains mtDNA (n = 20; cytochrome B, p = 0.0002 and 7S, p = 0.006), and anti-mitochondrial antibody Type 2 (n = 14; p = 0.001) as compared to normally developing, unrelated controls (n = 12). Extracellular blood mtDNA and other components may characterize an autistic endophenotype and may contribute to its pathogenesis by activating autoimmune responses."
Here are two more quotes that discuss the possible implications of these findings:
"The presence of extracellular mtDNA in children with autism suggests that it may be one source of "autoimmune" triggers, and may potentially explain some aspects of immune dysregulation reported in autistic patients. For instance, mtDNA (or other extracellular mitochondrial components not measured in this study) could activate TLRs on immune or glial cells to release pro-inflammatory cytokines, such as IL-6, IL-8 or TNF, high gene expression of which was reported in brains of autistic children."
And..
"One possibility is that mt (mitochondrial) components are secreted from immune cells, as was recently reported for activated neutrophils.[22] Another possibility could be activated tissue mast cells in the gut, where NT [23]is abundant and may induce mucosal permeability.[24] Our current findings showing that NT can trigger mtDNA release from human mast cells is supported by our previous report that NT, found both in the brain and the gut was elevated in autistic children."
This last quote hints at several interesting possible connections. The authors of the study have already reported that they found elevated levels of a peptide called neurotensin (NT) in children with autism, and here they are saying that NT is found in higher elevations in the gut and brain and may cause gut permeability which is known to be common in autism and itself leads to a cascade of problems as substances are able to leak from the gut into the bloodstream which aren't supposed to be there. Also, it has been noted that when there is gut permeability there is more likely to be permeability of the blood brain barrier. If elevated NT levels also cause permeability of the blood brain barrier that would also lead to a cascade of events that we see in autism such as mercury and pathogens in the brain.
