Genetics, Brain Structure, and Behavior Presentation

By: Jamie Berthelette, Denise Killiany, Julie Beach, Leah Bridges, and Mera Som

ALZHEIMERS DISEASEWhat is Alzheimer’s Disease?

Courtesy of: Drug Development Technology

The brain is made up of three major partsCerebral Cortex- Frontal, parietal, occipital,

and temporal lobesLimbic System- Hippocampus, amygdala, and

thalamusBrain Stem- Cerebellum, pons, and medulla

oblongata

Behavioral and Function changes that can occur with ADLimbic system damage impairs a person’s

memory and causes bad mood swingsCerebral cortex damage results in trouble

controlling emotional outbursts. People at this stage may even need help with eating, shaving, and combing their hair

Brain stem damage late in AD impairs organ functions which includes the function of the heart, lungs, and various other bodily processes

SUSPECTED OR KNOWN CAUSES OF ALZHEIMER’SResearch

Hypothesis about Alzheimer’s

Mutations associated with Alzheimer’s disease

Risk factors Traumatic head

injuries associated with Alzheimer’s

3M of Human Brain in Alzheimer’s Disease. Courtesy of: Sciencephoto.com

National Incidence of Alzheimer’s Disease

Who develops Alzheimer’s Disease10% of 65year old are at risk50% of 85 years old are at riskRare cases 2-5% of 40-50 years are at riskUnited States expected to have 14 million people with

Alzheimer’s Disease by the year of 2050

There are two ways of developing the Alzheimer’s disease. One, by the risk factors for Alzheimer’s disease occurs

mostly after 70 years old and through some rare cases of 40 - 50 years old people.

The other risk is by the gene of the parents or grandparents who suffered from Alzheimer’s Disease. Some children have the fifty percent risk.

More ways to have the risk of Alzheimer’s disease is by developing some of the following diseases:

High blood pressureCoronary artery diseaseDiabetesElevated blood cholesterolAlso including the individuals who have less

than eight years of education also have an increase of Alzheimer’s disease

The Genetics of DiseaseSome diseases are caused

by genetic mutation Permanent change in one

or more specific genes Defective genes come from

the parent.Other diseases are caused

by a genetic variant. Change in a gene can

cause a disease directly. When a genetic variant

increases but does not cause disease it is called a genetic risk factor.

Current TreatmentsNo cure for Alzheimer’s disease has been found to date.

Treatment for the disease is specifically aimed at assisting with the patient’s cognitive and behavioral symptoms.

Scientists and researchers are actively seeking out original treatments for pharmaceutical and non-drug treatment

modalities to assist in combating the disease.

Pharmaceutical Options (cont.)In order to combat the destructive process of the disease, Alzheimer’s drugs are given to support communication processes. Communication is supported through two unique mechanisms:

Cholinesterase inhibitors work by slowing down the disease activity that breaks down a key neurotransmitter. Donepezil, Galantamine, Rivastigmine and Tacrine are cholinesterase inhibitors.

Memantine, the fifth Alzheimer's drug, is an NMDA (N-methyl-D-aspartate) receptor antagonist, which works by regulating the activity of glutamate, a chemical messenger involved in learning and memory. Memantine protects brain cells against excess glutamate, a chemical messenger released in large amounts by cells damaged by Alzheimer's disease and other neurological disorders. Attachment of glutamate to cell surface "docking sites" called NMDA receptors permits calcium to flow freely into the cell. Over time, this leads to chronic overexposure to calcium, which can speed up cell damage. Memantine prevents this destructive chain of events by partially blocking the NMDA receptors (Alzheimer's Association, 2011).

Pharmaceutical OptionsCurrently there a five medications approved by the Food and Drug Administration for the treatment of Alzheimer’s Disease

Drug name Brand name Approved For FDA Approved

1. donepezil Aricept All stages 1996

2. galantamine Razadyne Mild to moderate 2001

3. memantine Namenda Moderate to severe 2003

4. rivastigmine Exelon Mild to moderate 2000

5. tacrine Cognex Mild to moderate 1993

Pharmaceutical Options (cont.)

In a healthy brain, neurons connect and communicate with one another at the synapses which carry information via neurotransmitters from cell to cell. In a patient with Alzheimer’s disease, the communication process is disrupted as the synapses and neurons are devastated by the malady, rendering them unable to communicate with the surrounding cells and thus slowly destroying the entire communication network.

A special note on stem cell research as applied to Alzheimer’s treatment Stem cells are cells in the body that can develop into any of the different

cell types needed to make a human being The ability of stem cells to turn into any cell type that the body needs

means that they have major potential to treat diseases where tissue has been damaged.

Stem cells can also grow into nerve cells and, as a result, have the potential to repair brain damage caused by neurological conditions.

Because of the loss of many different nerve cell types in the brain in Alzheimer's disease and the impact that the disease has on communication between cells, developing stem cell therapy for Alzheimer's disease is more complicated and challenging than for some other neurological conditions.

While it is unlikely that Alzheimer's disease will be one of the first diseases to benefit from advances in this area of research, it is possible that stem cell therapy may lead to advances in the treatment of people with Alzheimer's disease and other forms of dementia in the long term (Alzheimer's Society, 2011).

References Alzheimer's Association. (2011). Current Alzheimer's treatments. Retrieved from http://www.alz.org/research/science/alzheimers_disease_treatments.asp?type=more_information Alzheimer’s Association. (2011). [FDA-approved drugs] Current Alzheimer's Treatments. Retrieved

from http://www.alz.org/research/science/alzheimers_disease_treatments.asp?type=more_information Alzheimer's Association. (2011). Current Alzheimer's treatments. Retrieved from http://www.alz.org/research/science/alzheimers_disease_treatments.asp?type=more_information Centre de Neuropsychologie Belair. (2011). [Synapse] Neuropsychology for adults. Retrieved from http://www.centre-de-neuropsychologie.lu/personnesageeseng.html Alzheimer's Society. (2011). Stem cell research. Retrieved from http://www.alzheimers.org.uk/site/scripts/documents_info.php?documentID=430 Alzheimer’s Association. (2011). [Brain vasculature] Alzheimer’s Brain Tour. Retrieved from http://www.alz.org/research/science/alzheimers_brain_tour.asp Alzheimer’s Disease International (2010) World Alzheimer’s Report 2010 Retrieved 8.4.2011 from http://www.alz.co.uk/research/files/WorldAlzheimerReport2010ExecutiveSummary.pdf Alzheimer Society (2009). What is Alzheimer’s Disease? Retrieved from http://www.alzheimer.ca/english/disease/whatis-intro.htm Balci, B. D., Yener, G., & Angin, S. (2011). Journal of Neurological Science. Vol. 28 Issue 1, pp 51.

Retrieved from https://ehis.ebscohost.com/eds/results?sid Doctor Brunila, Nazario (2011) WebMD Slideshow: A Loved One Has Alzheimer’s Disease Retrieved

8.5.2011 from http://www.webmd.com/alzheimers/slideshow-alzheimers-overview Doctor Howard, Crystal (2011) Alzheimer’s Disease Retrieved 8.4.2011 from medicine.net

http://www.medicinenet.com/alzheimers_disease_causes_stages_and_symptoms/article.htm Shiel, W. C., Schoenfield, L. J. PhD. (1996-2011). What are causes of Alzheimer’s Disease? Retrieved from http://www.medicine.net/alzheimers_disease_causes_stages_and_symptoms/article.htm