Luteinizing Hormone and the Development of Alzheimer's

July 03, 2017

Lutienizing Hormone and the Development of Alzheimer’s 

 ReferencesHorm Behavior 2015PNASNeurobiolog AgingScience Daily

 Luteinizing hormone rises sharply with menopause. It is the hormone that stimulates egg production and ovulation in women, and sperm/testosterone production in men. The ovaries no longer respond to the effect of FSH and LH, and their rise marks the definitive marker of menopause. Hormone levels fall. Hot flashes, hair loss, lousy sleep, etc all ensue. Misery. Sorting out the confusion is no mean feat, particularly because there remains widespread confusion over the elevation of breast cancer risk with post menopausal hormone replacement. This confusion stems primarily from not recognizing the adverse affects of non-human estrogen compared to the beneficial effects of bio-identical human estrogen. 

 There is a legitimate question in there. Is it lack of estrogen that is dangerous, or the rise in the hormones that encourage the secretion of estrogen, namely luteinizing hormone. What effect does long term LH have on the female brain? That's the question raised here. How is the lack of Estrogen and Progesterone played out? Is it the lack of Estrogen that is the issue, or the damaging effect of too much LH? 

That's what this week's article is about, the possible role of LH in causing Alzheimer's. The authors carefully review the animal literature that demonstrates the damaging effect of high levels of HCG on rodent brains. HCG is very similar to LH, differing by only in the beta subunit, and is shown to have the same experimental effects on brains, namely an increase in amyloid beta proteins, neurofibrillatory tangles, and decreased problem solving ability. 

With menopause, LH rises sharply. With surgical menopause, it happens faster still. Epidemiological studies do link higher levels of LH in elderly women to more Alzheimer's. What does it take to suppress LH? You can do it with balanced hormones, which includes testosterone. Estrogen alone doesn't do it.   It takes estrogen, testosterone and progesterone to fully suppress LH. Progesterone can be shown to do it within 90 minutes of administration, but it's through an Estrogen dependent receptor. 

 Now, it's not total Estrogen that appears to have a protective effect but rather free estrogen. That's the nuance. There have been conflicting reports about estrogen not being protective for Alzheimer's, at least when simple total levels are measured. But when Sex Hormone Binding Globulin (SHBG) is measured, one gets a reflection of actual free (biologically active) estrogen levels. SHBG binds 99% of estrogen, so its level strongly reflects free estrogen (the remaining 1%). Measuring total Estrogen will not give a sufficiently detailed picture of the actual hormonal milieux of the aging female brain. High SHBG has been correlated with Alzheimer's. We do know that the use of birth control pills raises SHBG in women FOREVER, even after short periods of use. And we know that birth control pills alter women's brain, changing the nature of women's memory: emotional impact is improved, memory of details are lost. 

There are multiple studies showing that cognitive decline is reduced with birth control pills, which seems to suggest they are protective. What has not been done yet is a study looking at the risk of Alzheimer's disease after using the pill in young adulthood. So this is a real rat's nest of conflicting issues. The bottom line appears to be that LH may be the mediating factor in cognitive decline, but that occurs in the absence of adequate normal hormonal levels. If those levels are replaced, perhaps the measurement of LH should be a consideration for proper full replacement therapy, as that is the actual causative agent for damage. The lower, the better. And for men, with low testosterone, is the use of Clomid, an LH agonist, safe? We have no information. As long as it is raising T, it probably is, but this remains an issue to watch closely. 

 www.What will work for me. This appears to be an issue we have to understand. There is emerging consensus that human estrogen is good for the human female brain, and testosterone for the human male brain. Is the role of that utility come from suppressing LH. Something to be closely monitored. Stay tuned.   

 Pop Quiz

  1. Luteinizing hormone can be shown to make the pathology of Alzheimer's occur in rat.    T or F                                                                                                                         Answer: Probably true. Most of the rat research has been dose using HCG which is very close to LH, with very similar actions but a much longer half life.
  2. LH levels drop with menopause. T or F                                   Answer. False, false, false. It's the high levels of menopause that are the whole problem, and thereafter, Alzheimer's begins to show up.
  3. This would suggest that women who go through menopause earlier, have the onset of dementia earlier. T or f                                               Answer: True
  4. The confusion over risks for hormone replacement therapy are mostly from the confusion over bio-identical hormones versus artificial. T or F                              Answer: repeatedly, true.
  5. Do you want to know you LH levels?                                      Answer: I think I do.