Memory improvement following induced hyperinsulinemia in alzheimer's disease

doi:10.1016/0197-4580(95)02002-0

Neurobiology of Aging

Volume 17, Issue 1, January–February 1996, Pages 123-130

https://doi.org/10.1016/0197-4580(95)02002-0 Get rights and content

Abstract

Dementia of the Alzheimer type (DAT) is accompanied by disruption in glucose regulation and utilization that may contribute to its characteristic memory impairment. Increasing glucose availability by raising plasma glucose improves memory in patients with DAT. Such memory improvement is associated with a secondary elevation in plasma insulin levels, raising the question of whether improvement is due to changes in insulin levels, independent of hyperglycemia. Distributions of insulin receptors in the hippocampus and insulin-mediated increases in glucose utilization in entorhinal cortex provide potential mechanisms for such improvement. We show that raising plasma insulin through intravenous infusion while keeping plasma glucose at a fasting baseline level produces striking memory enhancement for patients with DAT. Previous findings of hyperglycemic memory enhancement were also replicated. Patients with DAT also showed abnormal plasma levels of glucoregulatory hormones and metabolites at baseline and during metabolic manipulations. Our findings suggest that neuroendocrine factors play an important role in the pathophysiology of DAT.

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ArticleMemory improvement following induced hyperinsulinemia in alzheimer's disease

Abstract

J. Biol. Chem.

Behav. Brain Res.

Biol. Psychiatr.

Adv. Metab. Disorders

Neurobiol. Aging

Neurosci. Lett.

Behav. Neural Biol.

Brain Res.

Neuropsychologia

Int. J. Dev. Neurosci.

Neurosci. Res.

Behav. Neural Biol.

Neurosci.

Visuospatial judgement: A clinical test

Arch. Neurol.

Mild senile dementia of the Alzheimer type: Research diagnostic criteria, recruitment, and description of a study population

J. Neurol. Neurosurg. Psychiatr.

Changes in blood glucose in patients with Senile Dementia of Alzheimer Type

Acta Med. Scand.

The effects of hyperglycemia on memory and hormone levels in Dementia of the Alzheimer type: A longitudinal study

Behav. Neurosci.

Glucose and memory in mild senile dementia of the Alzheimer Type

J. Clin. Exp. Neuropsychol.

Estrogen replacement therapy and neuropsychological performance in women with probable Alzheimer's disease: A case-control study

Neurology

Article
Memory improvement following induced hyperinsulinemia in alzheimer's disease