We observed in patients with T2D a higher percentage of H3Cit+ and MPO+ in both HDNs (3.8-fold and 6.1-fold; p < 0.001) and LDNs (2.1-fold and 5.9-fold; p < 0.001) compared to HVs (Figure 3A,C). Here, MPO is linked to type 2 diabetes mellitus.