Chronic alcohol abuse can lead to the degeneration of genes in the brain that recognize insulin. The resulting effects are comparable to neurological deterioration’s that often result from type 2 diabetes.
Researchers used postmortem human tissue to show that high levels of alcohol consumption over long periods of time leads to lower levels of genes needed to respond to insulin and insulin growth factor (IGF). This gene deficiency and lack of recognition of insulin leads to further brain damage.
The tissue came from six deceased chronic alcoholic, all male, with an average of 57.7 years of age, and six deceased “controls,” who were not alcoholics and had an average age of 57.5 years.
Type 2 diabetes is characterized by decreased sensitivity in the body to insulin production, and the resistance to insulin. Having an inability to recognize insulin due to brain function, which is what appears to happen with heavy alcohol use, seems to mimic these type 2 diabetes conditions.
Speaking of insulin, study author Dr. Suzanne de la Monte says “It has many functions, including regulation of metabolism. Cells throughout the body depend upon insulin just to stay alive and carry out ‘ordinary daily functions.’ The best known diseases associated with abnormalities in insulin’s availability or actions are Type 1 and Type 2 diabetes.
The role insulin plays on the brain is a relatively new field of research, but past studies have shown that decreased response in the brain to insulin can lead to neurological diseases, such as Alzheimer’s. According to Dr. de la Monte, “in either high concentrations, or at lower levels over a longer period of time, alcohol will dissolve some of the lipid in the cell’s membrane.” This
is what causes the decreased level of response to insulin, since IGF receptors are typically a part of the cell membrane.
The study went on to show more specifically that “Insulin and IGF resistance in the cerebellum and frontal lobe was associated with loss of neurons and their connections, and decreased levels of neurotransmitters needed for learning, memory, and motor function. The damage that we saw in the cerebellum would account for the poor balance, and increased rates of falling and trauma we see in alcoholics. The insulin and IGF resistance in alcoholics’ frontal lobes would account for their associated problems in memory.” The cerebellum and frontal lobe are characteristically the two regions in the brain most damaged by alcohol abuse.
These defects caused by alcohol abuse are very similar to symptoms of type 2 diabetes. “Our study indicates that chronic alcohol abuse causes a Type 2 diabetes effect in certain brain regions,” says Dr. de la Monte. This discovered parallel could be very beneficial in that neurological conditions caused by alcoholism (such as early stage Alzheimer’s disease), might be able to be treated in similar ways as type 2 diabetes is treated. In other words, drugs which increase insulin sensitivity and decrease insulin resistance might help limit brain damage caused by alcoholism.
Source: Defeat Diabetes Foundation: de la Monte, Suzanne. Alcoholism: Clinical & Experimental Research press release. June 2008.