RE: hyperglycemia causes poor memory

[Guest guest]

Hi Pat,

Interesting article. I could see this but have seen the other side as well.

If you have severe hypoglycemia and pass out from it too many times you too

can have cognitive damage. So, obviously, the extremes on either end can be

damaging. So let's be careful and watch those b.g.s!

Ruth

From: blind-diabetics

[mailto:blind-diabetics ] On Behalf Of LaFrance-Wolf

Sent: Wednesday, January 07, 2009 9:56 PM

To: Blind-DiabeticsYahoogroups (DOT) Com; Acb-DiabeticsAcb (DOT) Org; Doc Mahaber

Dr.; Cantrell

Subject: hyperglycemia causes poor memory

This article originally posted January 6, 2009 and appeared in

Issue 450

Hyperglycemia Not Hypoglycemia Alters Neuronal Dendrites and Impairs Memory

Hyperglycemic component of diabetes has a greater adverse effect on brain

functioning than does intermittent hypoglycemia.

It was previously reported that chronic hyperglycemia, and not hypoglycemia,

was associated with the reduction of neuronal size in the rat brain. So it

was hypothesized that hyperglycemia-induced changes in neuronal structure

would have negative consequences, such as impaired learning and memory. We

therefore

assessed the effects of hyperglycemia and hypoglycemia on neuronal dendritic

structure and cognitive functioning in young rats.

Experimental manipulations were conducted on male Wistar rats for 8 wk,

beginning at 4 wk of age. At the completion of the treatments, all rats were

trained

in the radial-arm water maze, a spatial (hippocampus-dependent) learning and

memory task. Three groups of rats were tested: an untreated control group,

a streptozotocin-induced diabetic (STZ-D) group, and an intermittent

hypoglycemic group. Following behavioral training, the brains of all animals

were

examined with histologic and biochemical measurements.

The results showed that peripheral hyperglycemia was associated with

significant increases in brain sorbitol and inositol and reduced taurine.

Histologic

evaluation revealed neurons with reduced dendritic branching and spine

density in STZ-D rats but not in control or hypoglycemic animals. In

addition, the

STZ-D group exhibited impaired performance on the water maze memory test.

From the results it was concluded that, hyperglycemia, but not hypoglycemia,

was associated with adverse effects on the brain polyol pathway activity,

neuronal

structural changes, and impaired long-term spatial memory. This finding

suggests that the hyperglycemic component of diabetes has a greater adverse

effect

on brain functioning than does intermittent hypoglycemia.

Pediatr Diabetes.