NOD1 and obesity due to melanocortin 4 receptor deficiency: For example, HFD-induced obesity has been shown to be a strong activator of the unfolded protein response (UPR) in mouse liver, which can be ameliorated through the NOD1 and NOD2 dampening actions of troxerutin, a derivative of natural bioflavonoid rutin found in tea, coffee, and many fruits and vegetables.