Every 67 seconds someone in the United States develops Alzheimer’s disease. Two thirds of these are women. Early symptoms are characterised by a difficulty remembering new information.
As the disease progresses it spreads to other functions of the body. The deposition of beta amyloid plaques and tau protein tangles build inside cells and eventually cause the death of neurons that control memory, personality, and those that regulate basic metabolic processes and physiologic function.
Consequently, Alzheimer’s Disease (AD) is now the 6th leading cause of death in the US – responsible for more deaths than prostate and breast cancer combined.
There are many ideas about what contributes to AD including insulin resistance (AD has been referred to as Type 3 diabetes), exposure to toxins and heavy metals, uncontrolled inflammation, food intolerances and changes in neurotransmitter levels. There is a significant decline in the production of a neurotransmitter called acetylcholine with AD patients, and a relationship between this and changes in hormone levels.
This may be one of the reasons that the disease disproportionately affects women. Estrogen stimulates the synthesis of acetylcholine and increases the number of synapses in the hippocampus, a part of the brain that is integral to memory storage. Additionally, estrogen protects the brain from oxidative stress, amyloid B peptide and glutamate induce toxicity. In fact, estrogen replacement has been shown to improve memory and cognition in women with Alzheimer’s disease and may modulate the risk of developing AD in the first place.
Progesterone is well established as an anti-inflammatory agent in the brain and can increase brain-derived neurotrophic factor (BDNF), an important agent that supports the survival of neurons and encourages the growth of new ones. Progesterone also protects against amyloid B-peptide toxicity, the main component in the amyloid plaques found in the brains of Alzheimer patients.
The restoration of balanced hormones is an integral part of the treatment for Alzheimer’s disease and maintaining optimal hormone levels may help to protect against the damage and degeneration that leads to the disease in the first place.
There has also been an association between Alzheimer’s and the head & neck (dys)realtionship. Dr. Michael Flanagan’s book, “The Downside of Upright Posture” is an excellent review of the anatomical link to this neurodegenerative disease (along with multiple sclerosis and parkinson’s).
- de la Monte SM, Wands JR. Alzheimer’s disease is type 3 diabetes – evidence reviewed. J Diabetes Sci Technol. Nov 2008; 2(6):1101-1113.
- Hu XY, et al. Decreased estrogen receptor-alpha expression in hippocampal neurons in relation to hyperphosphorylated tau in Alzheimer patients. Acta Neuropathol. 2003 Sep;106(3):213-20.
- Sribnick EA, et al. Estrogen attenuates glutamate-induced cell death by inhibiting Ca2+ influx through L-type voltage-gated Ca2+ channels. Brain Res. 2009 Jun 18;1276:159-70. Epub 2009 Apr 21.
- Gonzales GF, Carillo C. Blood serotonin levels in postmenopausal women: effects of age and serum oestradiol levels. Maturitas. 1993;17:23-9.
- Brann D, et al. Oestrogen signalling and neuroprotection in cerebral ischaemia. J Neuroendocrinol. 2012 Jan;24(1):34-47.
- Bartus RT, Dean RL, 3rd, Beer B, Lippa AS 1982 The cholinergic hypothesis of geriatric memory dysfunction. Science 217:408-414
- Gabor R, Nagle R, Johnson DA, Gibbs RB. Estrogen enhances potassium-stimulated acetylcholine release in the rat hippocampus. Brain Res. 2003 Feb 7;962(1-2):244-7.
- Van Amelsvoort T, Murphy DGM, Robertson D, Daly E, Whitehead M, Abel K. Effects of long-term estrogen replacement therapy on growth hormone response to pyridostigmine in healthy postmenopausal women. Psychoneuroendocrinology. 2003. 28,101-112.
- Wharton W, Baker LD, Gleason CE, Dowling M, Barnet JH, Johnson S, Carlsson C, Craft S, Asthana S. Short-term hormone therapy with transdermal estradiol improves cognition for postmenopausal women with Alzheimer’s disease: results of a randomized controlled trial. J Alzheimers Dis. 2011;26(3):495-505.
- Craig MC, Murphy DG. Estrogen therapy and Alzheimer’s dementia. Ann N Y Acad Sci. 2010 Sep;1205:245-53.
- Flanagan, M. The Downside of Upright Posture. June 2010.
- Labombarda F, et al. Progesterone and the spinal cord: good friends in bad times. Neuroimmunomodulation. 2010;17(3):146-9. Epub 2010 Feb 4.
- Goodman Y, et al. Estrogens attenuate and corticosterone exacerbates excitotoxicity, oxidative injury, and amyloid beta-peptide toxicity in hippocampal neurons. J Neurochem. 1996 May;66(5):1836-44..
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