Month: June 2025

Taurine and mitochondrial health

gettingwell4 4-5 stars Advanced knowledge, Immune system, Stress

A 2025 review subject was taurine’s beneficial effects on mitochondria:

“Taurine has multiple and complex functions in protecting mitochondria against oxidative-nitrosative stress. We introduce a novel potential role for taurine in protecting from deuterium (heavy hydrogen) toxicity. This can be of crucial impact to either normal or cancer cells that have highly different mitochondrial redox status.

Deuterium is an isotope of hydrogen with a neutron as well as a proton, making it about twice as heavy as hydrogen. We first explain the important role that the gut microbiome and gut sulfomucin barrier play in deuterium management. We describe synergistic effects of taurine in the gut to protect against deleterious accumulation of deuterium in mitochondria, which disrupts ATP synthesis by ATPase pumps.

Taurine’s derivatives, N-chlorotaurine (NCT) and N-bromotaurine (NBrT), produced through spontaneous reaction of taurine with hypochlorite and hypobromite, have fascinating regulatory roles to protect from oxidative stress and beyond. We describe how taurine could potentially alleviate deuterium stress, primarily through metabolic collaboration among various gut microflora to produce deuterium depleted nutrients and deuterium depleted water (DDW), and in this way protect against leaky gut barrier, inflammatory bowel disease, and colon cancer.

Taurine cannot be metabolized by human cells, but gut microbes are able to break it down to release sulfite, which then gets oxidized to sulfate anions that become available to support synthesis of sulfomucins. Taurine protects against many diseases linked to mitochondrial defects, such as aging, metabolic syndrome, cancer, cardiovascular diseases and neurological disorders.

We present a novel view that gut microbes play an essential role in providing deuterium depleted (deupleted) nutrients, especially, butyrate, to the host colonocytes forming the gut barrier. We propose that sulfomucins synthesized by goblet cells not only protect the barrier from pathogens, but also trap and sequester deuterium, thus reducing mitochondrial deuterium levels, resulting in improved mitochondrial health.

Due to taurine, redox buffer glutathione (GSH) further stabilizes the membrane potential. GSH not only reduces radical oxygen species (ROS) during oxidative stress, but it also assists in production of deupleted water in mitochondria.

Spontaneous oxidation of two GSH molecules to produce GSSG in the presence of hydrogen peroxide yields two molecules of DDW. Just as for glutathione, bilirubin can produce DDW indefinitely through chronic recycling between bilirubin and biliverdin, capturing a deupleted proton in NADPH to produce a DDW molecule in each cycle.

A novelty that arises from this investigation is introduction of the role that deuterium plays in mitochondrial disease, and ways in which taurine may facilitate maintenance of low deuterium in mitochondrial ATPase pumps. Excess deuterium causes a stutter in the pumps, which leads to inefficiencies in ATP production and an increase in ROS.”

https://pmc.ncbi.nlm.nih.gov/articles/PMC11717795/ “Taurine prevents mitochondrial dysfunction and protects mitochondria from reactive oxygen species and deuterium toxicity”

Stay away from NAC

gettingwell4 4-5 stars Advanced knowledge, Cortisol, Hypothalamus, Immune system, Limbic system, Neurochemicals, Stress

A 2025 rodent study added several reasons to avoid non-emergency use of N-acetylcysteine:

“We previously showed that antioxidants induced an impairment of negative feedback of the hypothalamus-pituitary-adrenal (HPA) axis in rats, in parallel to a down-regulation of glucocorticoid receptor (GR) and nuclear factor erythroid 2-related factor 2 (Nrf2) expression in the pituitary gland. This study evaluated the role of the Nrf2-heme-oxygenase-1 (HO-1) pathway on impairment of negative feedback of the HPA axis induced by N-acetylcysteine (NAC).

Male Swiss-Webster mice were orally supplemented with NAC for 5 consecutive days. The Nrf2-HO-1 pathway activator cobalt protoporphyrin IX (CoPPIX) was injected intraperitoneally on days 2 and 5 after starting NAC supplementation.

NAC reduced expression of Nrf2 in the pituitary of mice. NAC induced adrenal enlargement and hypercorticoidism, along with a decrease in GRα expression and an increase of GRβ expression in the pituitary gland.

We observed that dietary supplementation with NAC ( Figure 4A ) significantly increased plasma corticosterone levels in mice 24h ( Figure 4B ) as well as 15 days ( Figure 4C ) after the last administration of the antioxidant with the same magnitude of response (3.5-fold and 3.4-fold, respectively).

Chronic activation of the HPA axis can have damaging effects on immune, cardiovascular, metabolic, and neural functions, increasing the risk of immune system dysfunction, mood disorders, and metabolic and cardiovascular diseases. To prevent these deleterious effects of chronic hypercortisolism, HPA axis function is controlled by a glucocorticoid-dependent negative feedback system that is essential for ending the stress response.

These findings showed that NAC reduced Nrf2-HO-1 pathway activation in the pituitary gland, in a mechanism probably related to a local downregulation of GRα and an up-regulation of GRβ, leading to a failure of negative feedback of the HPA axis and consequently to the hyperactivity of this neuroendocrine axis.”

https://pmc.ncbi.nlm.nih.gov/articles/PMC11827418/ “Activation of the Nrf2/HO-1 pathway restores N-acetylcysteine-induced impairment of the hypothalamus-pituitary-adrenal axis negative feedback by up-regulating GRα expression and down-regulating GRβ expression into pituitary glands”

A human equivalent to this study’s NAC dose is (150 mg x .081) x 70 kg = 851 mg. Human supplements are sold in 600 mg and 1000 mg doses.

Grok 3 replied to a question: Human equivalent time to 15 days in male Swiss-Webster mice aged between 4 and 6 weeks? by stating: “15 days in male Swiss-Webster mice aged 4 to 6 weeks corresponds to approximately 4.1 human years, advancing their equivalent human age from about 10–12 years to roughly 14–16 years.” Four+ years seems like a long time for NAC to steadily and continuously affect humans’ HPA axes per the above graphic. What do you think?

Previously mentioned reasons to avoid daily use of NAC were in the lower part of A good activity for bad weather days.

Eat broccoli sprouts for your HIIT, Part 2

gettingwell4 2-3 stars Required further work, Epigenetics, Stress

A 2025 human study followed up Eat broccoli sprouts for your high intensity interval training using red kale sprouts:

“Glucosinolate-rich broccoli sprouts combined with intense exercise training for 7 days have been shown to reduce blood lactate concentrations during exercise, attenuate hypoglycemic events, improve physical performance, and reduce markers of oxidative stress. This study aimed to investigate the acute, dose-dependent effects of glucosinolate-rich red kale sprouts (GRS) on blood lactate and blood glucose following the ingestion of three different doses.

Fifteen healthy participants [11 females, 4 males] consumed 37.5 g or 75 g of GRS or an isocaloric placebo blended into a beverage on three separate occasions. The participants cycled on an ergometer at three submaximal work rates before and three hours after ingestion.

Intake of glucosinolate-rich sprouts acutely decreased blood lactate levels during submaximal cycling and increased blood glucose levels at rest. The largest reduction in blood lactate was observed at the 37.5 g dose compared to placebo.

To identify the dose of GRS that results in the lowest blood lactate concentration during submaximal exercise, we applied a quadratic modeling approach. The optimal dose for minimizing lactate accumulation was calculated as 44 g of GRS.

In our previous study, we found a tendency towards a lower respiratory exchange ratio after one week of supplementation. Moreover, studies have demonstrated that mitochondrial oxidation of long-chain and short-chain fatty acids is depressed in the absence of Nrf2, and accelerated when Nrf2 is constitutively active.

We observed a reduction in myeloperoxidase levels approximately three hours after GRS intake, suggesting a decrease in oxidative stress. This finding indicates that the adaptive compensatory system may act rapidly, likely within just a few hours of GRS consumption.

A limitation is that we did not assess whether the lower lactate levels translated into improved performance. Theoretically, if the reduction in lactate results from the activation of pyruvate dehydrogenase, it could enhance performance by channeling more pyruvate into mitochondria for efficient oxidation, reducing reliance on glycolysis, and thereby sparing muscle glycogen. Alternatively, if the lower lactate levels are due to increased activity of the hepatic Cori cycle, lactate could be more rapidly converted to glucose, possibly supporting glycogen resynthesis or maintaining blood glucose levels during exercise. Both mechanisms could potentially contribute to improved performance.

Acute intake of small doses of GRS followed by submaximal ergometer cycling results in changes in lactate and glucose metabolism that could be beneficial for exercise performance.”

https://www.biorxiv.org/content/10.1101/2025.04.15.648889v1.full “A glucosinolate-rich beverage lowers blood lactate concentrations during submaximal exercise”

These researchers chose red kale sprouts of undisclosed age over the predecessor study’s broccoli raab five-day old sprouts, and two other undisclosed cruciferous vegetable sprouts.

This study is in its preprint phase. Items that could be clarified before publishing in final form include:

  • In the Abstract section, reference findings to red kale sprouts rather than broccoli sprouts;
  • Characterize the lactate U-shaped dose-response curve as hormesis; and
  • Reference other hormesis findings for context.