Homocarnosine is a dipeptide composed of GABA and L-histidine that has been found in cerebrospinal fluid and the brain.¹It inhibits lipid peroxidation induced by AAPH when used at a concentration of 10 mM.²Homocarnosine (1 mM) decreases lactate dehydrogenase (LDH) and prostaglandin E₂release from PC12 cells in anin vitromodel of ischemia induced by oxygen-glucose deprivation.³It reduces infarct area and neurological deficit scores in a rat model of cerebral ischemia-reperfusion injury induced by middle cerebral artery occlusion (MCAO).⁴Homocarnosine (5 mg/animal) reduces mortality in a mouse model of subcutaneousS. aureusinfection.⁵

1.Crush, K.G.Carnosine and related substances in animal tissuesComp. Biochem. Physiol.34(1)3-30(1970) 2.Kohen, R., Yamamoto, Y., Cundy, K.C., et al.Antioxidant activity of carnosine, homocarnosine, and anserine present in muscle and brainProc. Natl. Acad. Sci. USA85(9)3175-3179(1988) 3.Tabakman, R., Lazarovici, P., and Kohen, R.Neuroprotective effects of carnosine and homocarnosine on pheochromocytoma PC12 cells exposed to ischemiaJ. Neurosci. Res.68(4)463-469(2002) 4.Huang, J., Wang, T., Yu, D., et al.L-Homocarnosine attenuates inflammation in cerebral ischemia-reperfusion injury through inhibition of nod-like receptor protein 3 inflammasomeInt. J. Biol. Macromol.118(Pt A)357-364(2018) 5.Mukkada, A.J., Nutini, L.G., and Cook, E.S.Prophylactic effects of γ-aminobutyrylhistidine (homocarnosine) on experimental staphylococcal infections in miceAppl. Microbiol.18(4)641-645(1969)