April 8th, 2024
Literature Review
1) In a first of its kind study in mice, we see concrete evidence for how the mitochondria in obese individuals are a root cause of disease based on nutritional input. From the study: "Mitochondrial dysfunction is a characteristic trait of human and rodent obesity, insulin resistance and fatty liver disease.
Here we show that high-fat diet (HFD) feeding causes mitochondrial fragmentation in inguinal white adipocytes from male mice, leading to reduced oxidative capacity by a process dependent on the small GTPase RalA. RalA expression and activity are increased in white adipocytes after HFD. Targeted deletion of RalA in white adipocytes prevents fragmentation of mitochondria and diminishes HFD-induced weight gain by increasing fatty acid oxidation. Mechanistically, RalA increases fission in adipocytes by reversing the inhibitory Ser637 phosphorylation of the fission protein Drp1, leading to more mitochondrial fragmentation. Adipose tissue expression of the human homolog of Drp1, DNM1L, is positively correlated with obesity and insulin resistance. Thus, chronic activation of RalA plays a key role in repressing energy expenditure in obese adipose tissue by shifting the balance of mitochondrial dynamics toward excessive fission, contributing to weight gain and metabolic dysfunction." (Xia et. al. 2024)
This fascinating animal translational study gives us insight into how a high fat diet is also a major component of mitochondrial damage through fission and fragmentation leading to worsened cell bioenergetics. The cells have reduced fatty acid oxidation or fat burning capacity due to a single gene's actions. The end result is a tilt toward fat cell production, fat storage and fat cell inflammation which are associated with diabetes and insulin resistance and ultimately metabolic syndrome.
This starts to explain the paradox that is obesity where the person has a ton of stored energy, but has limited capacity to utilize it. It is like having a gas tank of fuel with a gas line that only allows for 1/10th of the flow required for optimal function. Science Daily has an excellent review of this paper. Link below.
2) Women's brains change during pregnancy as per a new study. The authors looked at brain changes before and after birth as well as with or without a vaginal delivery route. Their study findings noted transient changes in some brain regions as well as permanent changes in other brain regions that turn on self-reflection and empathy for others. The default mode network (DMN) turns on when we are not task oriented, i.e. day dreaming. This area is up regulated which would propose that its enhancement is for the maternal child bond strengthening. The study notes that the DMN does not ever regain prepregnancy size positing that this change is permanent and necessary. This, to me, reinforces the evolutionary need of the DMN to help foster mother child attachment which is critical to species survival.(Paternina-Die et. al. 2024)
You may ask why a reduction in the DMN size would correlate with more DMN activity? The answer lies in selective neuronal pruning to emphasize certain important pathways while other less important pathways are pruned. This happens at many different stages of life while we sleep to enhance necessary memories and down play unimportant ones. The brain is very adept at selective pruning for species benefit. Mothers and their children will selectively prune certain neuronal pathways for a collaborative attachment and loving bond.
My question is this, what blocks this from happening in certain poorly attached/bonded mother child dyads? I suspect that maternal trauma is at the root. TBD.
3) Bananas have an enzyme inside them called polyphenol oxidase (PPO) that blocks the absorption of poly phenolic compounds from other foods like blueberries. Flavan 3 ols are a specific beneficial chemical found in many fruits and vegetables that are reduced by the polyphenol oxidase enzyme limiting their potential benefit. From the study: "To assess whether or not consuming freshly prepared smoothies made with different PPO-containing fruit impacts the bioavailability of the flavan-3-ols, a controlled, single blinded and cross-over study was conducted in healthy men (n = 8) who consumed a flavan-3-ol-containing banana-based smoothie (high-PPO drink), a flavan-3-ol-containing mixed berry smoothie (low-PPO drink) and flavan-3-ols in a capsule format (control). The peak plasma concentration (Cmax) of flavan-3-ol metabolites after capsule intake was 680 ± 78 nmol L−1, which was similar to the levels detected after the intake of the low PPO drink. In contrast, the intake of the high PPO drink resulted in a Cmax of 96 ± 47 nmol L−1, 84% lower than that obtained after capsule intake. In a subsequent study (n = 11), flavan-3-ols were co-ingested with a high-PPO banana drink but contact prior to intake was prevented. In this context, plasma flavan-3-ol levels were still reduced, suggesting an effect possibly related to post-ingestion PPO activity degrading flavan-3-ols in the stomach. There was a substantial range in the PPO activity detected in 18 different fruits, vegetables and plant-derived dietary products. In conclusion, bioavailability of flavan-3-ols, and most likely other dietary polyphenol bioactives, can be reduced substantially by the co-ingestion of high PPO-containing products, the implications of which are of importance for dietary advice and food preparation both at home and in industrial settings." (Ottaviani et. al. 2023)
This is a very small study. However, the effect is clear in the food interaction. If the enzyme PPO is found in high volume in the food that is consumed, in this case a banana, then the beneficial F3ols will be degraded and not available for your health. Take home: limit the consumption of bananas with F3ols.
F3ol foods are: berries, cocoa, tea, pecans, apples, peaches, wine.
4) My friend Francis Koster has been beating the drum of indoor air quality in schools for years. Now in the journal Science we see an article entitled: Mandating indoor air quality for public buildings,
If some countries lead by example, standards may increasingly become normalized. The article is worth a read. Public schools and public spaces need to exchange indoor air hourly like an airplane. The end result would be increased mentation, reduced infectious disease transfer, reduced mold and dust formation and so much more. Oh and by the way, this is how it has always been for millennia. (Morawska et. al. 2024)
Upcoming podcast with Francis will unravel this story much more. Stay Tuned!
Dr. M
