Effective interventions that provide obvious neuroprotection are currently fairly limited.
Glucagon-like peptide-1 (GLP-1), an enhancer of
insulin production with a trophic effect on β cells in the islets, has been found to be trophic for neuronal cells.
Alogliptin benzoate (AGL), a selective inhibitor of dipeptidylpeptidase-4 (DPP-4) functioning as a long-acting agonist of
GLP-1, is in clinical use worldwide for patients with
diabetes mellitus type 2. To clarify whether administration of AGL, independent of the insulinotropic effect, protects the brain against focal
ischemia, we investigated the effect of AGL on the development of
cerebral infarction in non-diabetic normal mice. Male C57BL/6J mice were administered AGL (7.5, 15, or 30μg) once a day for three weeks by intragastric gavage. After the induction of temporary focal
ischemia, volumes of infarcted lesions and neurological deficits were analyzed at 24h (acute phase) and seven days (chronic phase). In the acute phase, significant reductions were observed in the volumes of infarcted lesions (p=0.009), and in the severity of neurological deficits (p=0.004), in the group treated with 15μg of
alogliptin benzoate, but not the 7.5 or 30μg-treated groups. This significant reduction in volumes of infarcted lesions persisted into the chronic phase. At the end of the AGL treatment; before the induction of
ischemia, the levels of
brain-derived neurotrophic factor (
BDNF), a potent
neuroprotectant in the brain, were elevated in the cortex (p=0.008), or in the whole forebrain (p=0.023). AGL could be used as a daily
neuroprotectant or an enhancer of
BDNF production aiming to attenuate cerebral
injuries, for the growing number of people who have the risk of
ischemic stroke.