Single mutation in peptide inhibitor of TRPV1 receptor changes its effect from hypothermic to hyperthermic level in animals

The TRPV1 receptor plays a significant role in many biological processes, such as perception of external temperature (above 43°C), inflammation development, and thermoregulation. Activation of TRPV1 leads to the pain occurrence and decrease in the body temperature, while inhibition of this receptor can lead to an increase in the temperature. The TRPV1 peptide modulators from sea anemone Heteractis crispa extract (APHC1 and APHC3) have been previously characterized as molecules, which generated a pronounced analgesic effect and a decrease in the body temperature in experimental animals. Using the combined APHC1 and APHC3 amino acid sequences, we have prepared a hybrid peptide molecule named A13 that contains all residues potentially important for the activity of the peptide precursors. Biological tests on animals have shown that the hybrid molecule not only combines the analgesic properties of both peptides but, unlike the peptide precursors, also raises the body temperature of experimental animals.