Mitochondrial alterations and tendency to apoptosis in peripheral blood cells from children with Down syndrome

Different types of cells from subjects with Down syndrome (DS) have an increased susceptibility to cell death. We have studied apoptosis and mitochondrial (mt) membrane potential (ΔΨm) in peripheral blood mononuclear cells (PBMC) from DS children and age-matched healthy donors after in vitro treatment with apoptogenic molecules, along with mtDNA content. We found that PBMC from DS and healthy controls had a similar tendency to undergo apoptosis and a similar amount of mtDNA. However, in cells from DS subjects, mitochondria showed a higher loss of ΔΨm, underlying the presence of an increasing susceptibility of these organelles to damaging agents.