Nitric oxide synthase 2 (NOS2), upregulated in IBD patients (log2fc = 2.60[CD]; 3.49[UC]), was connected to the depletion of negative modulators such as L-arginine (pxC50 = 6.52, log10fc = −0.31[CD]; −0.19[UC]). Here, NOS2 is linked to inflammatory bowel disease.