The gut microbiota mediates the anti-seizure effects of the ketogenic diet, 2018, Olson et al

[Indigophoton]

I'm posting this because I've noticed some people mention finding a keto diet helpful for their ME.

It seems that the keto diet potentially - tbc in humans - results in a couple of key types of gut bacteria that are found to modulate levels of GABA in the brain. GABA is increased relative to the excitory neurotransmitter glutamate, thus calming brain activity.

So I wonder if those for whom keto is helpful are benefiting from the increased GABA (as, anecdotally at least, drugs and supplements that boost GABA are helpful to some pwme).

The study was in mice, so the results may not prove to apply to humans, but interesting so far. It seems like a nice set of experiments.

UCLA scientists have identified specific gut bacteria that play an essential role in the anti-seizure effects of the high-fat, low-carbohydrate ketogenic diet. The study, published today in the journal Cell, is the first to establish a causal link between seizure susceptibility and the gut microbiota—the 100 trillion or so bacteria and other microbes that reside in the human body's intestines.

The ketogenic diet has numerous health benefits, including fewer seizures for children with epilepsy who do not respond to anti-epileptic medications, said Elaine Hsiao, UCLA assistant professor of integrative biology and physiology, and senior author of the study. However, there has been no clear explanation for exactly how the diet aids children with epilepsy.

Researchers in Hsiao's laboratory hypothesized that the gut microbiota is altered through the ketogenic diet and is important for the diet's anti-seizure effects. Hsiao's research team conducted a comprehensive investigation into whether the microbiota influences the ability of the diet to protect against seizures and if so, how the microbiota achieves these effects.

The article, https://m.medicalxpress.com/news/2018-05-gut-bacteria-key-role-anti-seizure.html

• Graphical Abstract

Highlights

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  Changes in the gut microbiota are required for the anti-seizure effects of the KD
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  Specific KD-associated bacteria mediate and confer the anti-seizure effects of the KD
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  KD microbiota regulate amino acid γ-glutamylation and hippocampal GABA/glutamate

Summary
The ketogenic diet (KD) is used to treat refractory epilepsy, but the mechanisms underlying its neuroprotective effects remain unclear. Here, we show that the gut microbiota is altered by the KD and required for protection against acute electrically induced seizures and spontaneous tonic-clonic seizures in two mouse models. Mice treated with antibiotics or reared germ free are resistant to KD-mediated seizure protection. Enrichment of, and gnotobiotic co-colonization with, KD-associated Akkermansia and Parabacteroides restores seizure protection. Moreover, transplantation of the KD gut microbiota and treatment with Akkermansia and Parabacteroides each confer seizure protection to mice fed a control diet. Alterations in colonic lumenal, serum, and hippocampal metabolomic profiles correlate with seizure protection, including reductions in systemic gamma-glutamylated amino acids and elevated hippocampal GABA/glutamate levels. Bacterial cross-feeding decreases gamma-glutamyltranspeptidase activity, and inhibiting gamma-glutamylation promotes seizure protection in vivo. Overall, this study reveals that the gut microbiota modulates host metabolism and seizure susceptibility in mice.

The paper, https://www.cell.com/action/showImagesData?pii=S0092-8674(18)30520-8

Full paper here, http://sci-hub.tw/10.1016/j.cell.2018.04.027