Background

• Cyclo(His-Pro) is a naturally occurring molecule found in the brain, spinal fluid, and blood. It was first discovered in 1976 in the hamster hypothalamus, the region of the brain that regulates hunger, thirst, and body temperature.
• Cyclo(His-Pro) has been used as a dietary supplement. Limited research suggests that consuming cyclo(His-Pro) and zinc may help reduce blood sugar levels. However, more evidence is needed before conclusions can be made on the use of this supplement in improving blood sugar control.
• Preliminary evidence has found that cyclo(His-Pro) may improve zinc absorption and aid in wound healing and immune function, particularly in diabetic patients. Although confirmation is needed, supplementation with cyclo(His-Pro) plus zinc is a promising treatment for high blood sugar.

References

1. Bhargava, H. N. Antagonism of ketamine-induced anesthesia and hypothermia by thyrotropin releasing hormone and cyclo(His-Pro). Neuropharmacology 1981;20(7):699-702. View Abstract
2. Bhargava, H. N. Inhibition of abstinence syndrome in opiate dependent mice by cyclo (His-Pro). Life Sci 3-16-1981;28(11):1261-1267. View Abstract
3. Hwang, I. K., Go, V. L., Harris, D. M., Yip, I., Kang, K. W., and Song, M. K. Effects of cyclo (his-pro) plus zinc on glucose metabolism in genetically diabetic obese mice. Diabetes Obes.Metab 2003;5(5):317-324. View Abstract
4. Imamura, M. and Prasad, C. Cyclo (His-Pro) potentiates GABA/ethanol-mediated chloride uptake by neurosynaptosomes. Peptides 2003;24(3):445-448. View Abstract
5. Minelli, A., Bellezza, I., Grottelli, S., and Galli, F. Focus on cyclo(His-Pro): history and perspectives as antioxidant peptide. Amino.Acids 2008;35(2):283-289. View Abstract
6. Minelli, A., Bellezza, I., Grottelli, S., Pinnen, F., Brunetti, L., and Vacca, M. Phosphoproteomic analysis of the effect of cyclo-[His-Pro] dipeptide on PC12 cells. Peptides 2006;27(1):105-113. View Abstract
7. Minelli, A., Conte, C., Grottelli, S., Bellezza, I., Emiliani, C., and Bolanos, J. P. Cyclo(His-Pro) up-regulates heme oxygenase 1 via activation of Nrf2-ARE signalling. J Neurochem. 2009;111(4):956-966. View Abstract
8. Mizumo, H., Svec, F., Prasad, C., and Hilton, C. Cyclo(His-Pro) augments the insulin response to oral glucose in rats. Life Sci 1997;60(6):369-374. View Abstract
9. Prasad, C. Neuropeptide-dopamine interactions. II. Cyclo (His-Pro) augmentation of amphetamine- but not apomorphine-induced stereotypic behavior. Behav Brain Res 1988;27(3):241-245. View Abstract
10. Prasad, C. Role of endogenous cyclo(His-Pro) in voluntary alcohol consumption by alcohol-preferring C57BL mice. Peptides 2001;22(12):2113-2117. View Abstract
11. Rosenthal, M. J., Hwang, I. K., and Song, M. K. Effects of arachidonic acid and cyclo (his-pro) on zinc transport across small intestine and muscle tissues. Life Sci 12-7-2001;70(3):337-348. View Abstract
12. Song, M. K., Hwang, I. K., Rosenthal, M. J., Harris, D. M., Yamaguchi, D. T., Yip, I., and Go, V. L. Anti-hyperglycemic activity of zinc plus cyclo (his-pro) in genetically diabetic Goto-Kakizaki and aged rats. Exp.Biol Med (Maywood.) 2003;228(11):1338-1345. View Abstract
13. Song, M. K., Rosenthal, M. J., Hong, S., Harris, D. M., Hwang, I., Yip, I., Golub, M. S., Ament, M. E., and Go, V. L. Synergistic antidiabetic activities of zinc, cyclo (his-pro), and arachidonic acid. Metabolism 2001;50(1):53-59. View Abstract
14. Song, M. K., Rosenthal, M. J., Song, A. M., Uyemura, K., Yang, H., Ament, M. E., Yamaguchi, D. T., and Cornford, E. M. Body weight reduction in rats by oral treatment with zinc plus cyclo-(His-Pro). Br.J Pharmacol 2009;158(2):442-450. View Abstract
15. Suzuki, T., Sakurada, T., Tadano, T., Kisara, K., Sasaki, Y., and Suzuki, K. Effect of cyclic dipeptides containing histidine on pentobarbital narcosis. J Pharmacobiodyn. 1981;4(5):377-379. View Abstract