MOLECULE

Uridine 5'-diphosphate

Uridine 5'-diphosphate, also known as 5'-UDP or uridine diphosphoric acid, belongs to the class of organic compounds known as pyrimidine ribonucleoside diphosphates. These are pyrimidine ribonucleotides with diphosphate group linked to the ribose moiety. Uridine 5'-diphosphate is an important extracellular pyrimidine signaling molecule that mediates diverse biological effects via P1 and P2 purinergic receptors, such as the uptake of thymidine and proliferation of gliomas. Uridine 5'-diphosphate is an extremely weak basic (essentially neutral) compound (based on its pKa). Uridine 5'-diphosphate exists in all living species, ranging from bacteria to humans. Within humans, uridine 5'-diphosphate participates in a number of enzymatic reactions. In particular, tamoxifen-N-glucuronide and uridine 5'-diphosphate can be biosynthesized from tamoxifen and uridine diphosphate glucuronic acid through the action of the enzyme UDP-glucuronosyltransferase 1-4. In addition, 4-hydroxytamoxifen-O-glucuronide and uridine 5'-diphosphate can be biosynthesized from 4-hydroxytamoxifen and uridine diphosphate glucuronic acid through the action of the enzyme UDP-glucuronosyltransferase 1-4. In humans, uridine 5'-diphosphate is involved in tamoxifen metabolism pathway. Outside of the human body, Uridine 5'-diphosphate has been detected, but not quantified in, several different foods, such as pineapples, pine nuts, potato, swiss chards, and lima beans. This could make uridine 5'-diphosphate a potential biomarker for the consumption of these foods. Uridine 5'-diphosphate induces intracellular Ca(2+) responses and oscillations in HeLa cells, due to the activation of P2Ys (G-protein coupled ATP receptors). Uridine 5'-diphosphate is expected to be in Cannabis as all living plants are known to produce and metabolize it.