Women are more prone to Alzheimer's. Why?

It's well understood that women are more prone to develop Alzheimer's disease than men.  But, of course, women live longer than men.  So it stands to reason that by simply living longer, women will be more susceptible to any disease of old age.  But the numbers don't add up.  Women develop Alzheimer's in numbers too much greater than men to be simply accounted for by a longer life.  Women are also more likely to develop MS than men, but men are more likely to develop Parkinson's, brain tumors, and epilepsy.  Why is that?

I recently came across this interesting article that addresses possible explanations.  For Alzheimer's, two dynamics appear to be the differences in male and female chromosomes (XX for women and XY for men) and hormonal changes during menopause.

The X and Y chromosomes contain genes for sex differences.  However, while women have two X chromosomes, one of then is mostly silenced.  Mostly.  Those genes not silenced (on the chromosome that men lack) appear to be related to the immune system, brain function, and Alzheimer's disease.

The article discusses the consequences of hormonal changes during menopause, but sheds little light on how they might influence the development of Alzheimer's disease.  However, we did write about this back in 2018, with a link to a possibly more insightful article.  Or maybe not.  Mostly, they acknowledge that there must be a role for sex hormones in the development of Alzheimer's, but it's really not clear how that works.

Guts and Brains ... and More Amazing News

We've written before about the gut-brain axis, that mysterious communications system between the microbes in your gut and your brain.  Somehow, they support each other, and an unhealthy gut can mean an unhealthy brain.  So we do what we can to support a healthy gut.  Which means eating right and avoiding chemicals that kill gut microbes, like artificial sweeteners and animal products that might contain antibiotics.

Neurologists like to say that "what's good for the heart is good for the brain."  We might add to that, "What's good for the gut is good for the brain." 

Therefore, we might want to consume products with probiotic bacteria, like yogurt.  However, these microbes are often destroyed in the digestive process and don't always make it out of your stomach.  So there are supplements that can help with that.  And then there are the benefits of prebiotics, "fermentable soluble food fiber," which help supply the needs of the gut microbes.  A a high fiber diet is good for the gut ... which is good for the brain.

The research on the benefits of probiotics and prebiotics continues, and there's some amazing news.  There was a recent study published in Nature Communications using twins to study the effects of consuming prebiotic supplements on memory and cognition.  The results were pretty remarkable, even over a relatively short period of time.

The supplements were inulin, a dietary fiber in the fructan class, and fructooligosaccharide (FOS), a plant carbohydrate sometimes used as a natural low calorie sweetener.  Looking at a box of Costco nut bars, I see a form of inulin listed as an ingredient.  But asparagus is a great source for both inulin and FOS.  For this study, subjects were given supplements, either with both prebiotics or with a placebo.

The study was conducted by Kings College, London, and it used 36 pairs of twins over the age of 60.  One twin was given a daily prebiotic in a protein powder and the other was given a daily placebo in a protein powder.  After only twelve weeks, there was measurable improvement in cognition.  Using some of the same tests used to diagnose Alzheimer's disease, the prebiotic test subjects showed a significant improvement in a cognitive score compared to subjects who took the placebo.

Moral of the story?  Eat your vegetables, especially the leafy greens in the MIND diet!  And it wouldn't hurt to take inulin and FOS supplements.  They're known to be cheap.

There Is News Worth Sharing, But...

... but I've just been really lazy.  My last post to this blog was June 5.  Now it's a month later.

But I do watch the news on Alzheimer's disease and dementia, and I accumulate topics worth sharing.  Usually, I research each story and then try to break it down in a way that would interest most people.  But now, I've accumulated a significant backlog of topics, and I have no hope of researching them all.  But I will share what's come across my computer screen and try to give a little insight on each.  So here:

1.  Alzheimer's disease could be prevented by antiviral drugs already on market.  These are NRTIs, nucleoside reverse transcriptase inhibitors, that are antivirals approved to treat HIV infection, but scientists from UVA Health at the University of Virginia found that patients taking them were less likely to develop the common form of dementia.  Click here.

2.  New Alzheimer’s drug boosts brain protection, restores memory.  A promising drug candidate, DDL-357, improves memory in Alzheimer’s mouse models by increasing levels of a protective brain protein called clusterin (CLU). CLU helps prevent the buildup of toxic amyloid-beta plaques and tau proteins, both key drivers of Alzheimer’s disease.  Click here.

3.  Do viruses trigger Alzheimer's?  A growing number of researchers think so.  (And so do we.)  Click here.

4. SSRIs restore brain function in Alzheimer’s.  A new study suggests that SSRIs, commonly prescribed antidepressants, may reduce biological markers of Alzheimer’s disease. In a cohort of 191 individuals, AD patients on SSRIs had lower levels of plasma phosphorylated tau-181, a key indicator of disease severity.  Brain scans also showed that SSRIs restored metabolic activity in an early site of tau accumulation and serotonin production. This metabolic recovery was not observed in healthy individuals, suggesting a disease-specific effect.  Click here.

5.  Facial stimulation clears brain waste and boosts aging minds.  Researchers have discovered a safe, non-invasive way to enhance the brain’s waste clearance system by mechanically stimulating lymphatic vessels just beneath the facial skin. This gentle technique significantly improves cerebrospinal fluid (CSF) drainage—a critical function that declines with age and contributes to cognitive disorders like Alzheimer’s.  The team used fluorescent tracers in mice and monkeys to uncover a new drainage pathway connecting facial lymphatics to deep lymph nodes, which remains intact even in older individuals. A handheld device that lightly strokes the skin restored youthful CSF flow in aged animals, opening up exciting potential for wearable treatments that prevent or slow neurological decline.  Click here.

6.  The cause of Alzheimer's might be coming from within your mouth.  We wrote about this in Beating the Dementia Monster, but the case continues to grow.  So floss your teeth!  Click here.

7.  Are rosemary and sage the future of Alzheimer’s treatment?  The same herb that flavors your roast chicken is showing promising results in brain research.  Click here.  And here.

8.  Ketogenic diet raises brain blood flow by 22% and BDNF by 47% in new study.  In Beating the Dementia Monster, we said that BDNF was the key biochemical factor that made the Dementia Toolkit work.  Click here. 

9.  Human brains keep making memory neurons in adulthood.  In further confirmation of what we said in Beating the Dementia Monster, a groundbreaking study shows that the human hippocampus continues producing new neurons well into late adulthood. Researchers identified neural progenitor cells—the precursors to neurons—in adults up to 78 years old, confirming ongoing neurogenesis in the memory center of the brain.  Using advanced sequencing, imaging, and machine learning techniques, they traced how these cells develop and where they reside in the hippocampus. The findings may pave the way for regenerative therapies targeting cognitive and psychiatric disorders.  (Of course, as we wrote, BDNF prompts stem cells in the hippocampus form new neurons.). Click here.

10.  Surprise discovery about sugar in the brain could help fight Alzheimer's. Stores of glucose in the brain could play a much more significant role in the pathological degeneration of neurons than scientists realized, opening the way to new treatments for conditions like Alzheimer's disease. Click here.

11.  Spermidine is great for longevity, hair growth and heart health, says expert.  We discussed spermidine briefly in Beating the Dementia Monster.  Click here.