How Capsaicin Works: A Better Understanding By Jane Farrell Researchers are drawing closer to understanding how capsaicin helps the bodyΓÇÖs response to pain, and that may help in designing more effective pain treatments. Investigators from the University of California, Davis, reported their identification of molecular interactions with capsaicin in the journal Nature Chemical Biology. Capsaicin is the ingredient that makes chili peppers spicy and hot. According to a news release from the university, the same pathway in the body that responds to spicy food is also activated after injury or when the immune system mounts an inflammatory response to bacteria, viruses, or in the case of autoimmune disease, the bodyΓÇÖs own tissues. Senior author Jie Zheng, professor of physiology and membrane biology at UC Davis, said the researchers filled in important ΓÇ£atomic-level details about exactly how the capsaicin molecule interacts with TRPV1, one of the bodyΓÇÖs primary receptors for sensing pain and heat.ΓÇ¥ Using computer models based on atomic force fields and existing low resolution 3-D reconstructions of the TRPV1-capsaicin complex, the researchers identified several structural areas that enable capsaicin to strongly bind to the TRPV1 receptor. The new structural information may serve to guide the drug-design process, the researchers said. ΓÇ£Just as we can ΓÇÿget used toΓÇÖ a spicy dish by the end of the meal, we believe that there are ways to develop highly specific molecules that make TRPV1 less sensitive to painful stimuli,” Zheng said.