Description
Peptide histidine isoleucine (PHI) is an endogenous brain-gut peptide that activates VPAC2 receptors. PHI exhibits anorexigenic activity in vivo, decreasing feeding behavior in an oxytocin-mediated manner. PHI also decreases caspase 3 activity and increases glutamate transporter (GLT-1a) activity in vitro. This peptide inhibits proliferation of neuroblastoma cells in a MAPK-mediated manner and appears to play a role in circadian rhythm management.
References
Goursaud S, Focant MC, Berger JV, et al. The VPAC2 agonist peptide histidine isoleucine (PHI) up-regulates glutamate transport in the corpus callosum of a rat model of amyotrophic lateral sclerosis (hSOD1G93A) by inhibiting caspase-3 mediated inactivation of GLT-1a. FASEB J. 2011 Oct;25(10):3674-86. PMID: 21730107.
Colwell CS, Michel S, Itri J, et al. Disrupted circadian rhythms in VIP- and PHI-deficient mice. Am J Physiol Regul Integr Comp Physiol. 2003 Nov;285(5):R939-49. PMID: 12855416.
Olszewski PK, Wirth MM, Shaw TJ, et al. Peptides that regulate food intake: effect of peptide histidine isoleucine on consummatory behavior in rats. Am J Physiol Regul Integr Comp Physiol. 2003 Jun;284(6):R1445-53. PMID: 12595279.
Lelièvre V, Pineau N, Du J, et al. Differential effects of peptide histidine isoleucine (PHI) and related peptides on stimulation and suppression of neuroblastoma cell proliferation. A novel VIP-independent action of PHI via MAP kinase. J Biol Chem. 1998 Jul 31;273(31):19685-90. PMID: 9677397.