Figure 4.

Normal and abnormal (uremic) remote sensing and signaling. Please see text for a detailed explanation of the remote sensing and signaling theory of interorgan and inter-organismal (gut microbe–host) communication via small molecules that regulate metabolism, signaling, and oxidative state. The proteins mediating these effects of small molecules include transporters, drug metabolizing enzymes, and nuclear receptors. Some of the regulated molecules include gut microbe-derived uremic toxins.