Measuring gut microbiota, Part 2

A 2023 porcine study expanded Part 1’s coverage to include stomach and small intestine microbiota:

“Identification of individual intestinal microbes affecting phenotypes and diseases depends on statistical analyses between these two main variables. Because the phenotypes or diseases are typically well-defined, success of statistical analyses on these studies depend on precise elucidation of gut microbiome composition.

This work with genetically homogenous sibling pigs grown in a cohoused condition to minimize experimental errors showed that composition of the gut microbiome constantly changed in response to local environmental changes of the GI tract. Pigs are omnivorous and have the most similar digestive mechanisms to humans.

The stomach and small intestine microbiomes – which are rich in nutrients – were very different from the large intestine and feces microbiomes in terms of both composition and diversity. Firmicutes, Proteobacteria, Actinobacteria, Cyanobacteria, and Fusobacteria phyla were relatively more dominant in the stomach and small intestine than the large intestine and feces. Bacteroidetes was more heavily dominated in the large intestine and feces.

Sampling locations within the GI tract were determined based on their anatomical feature: stomach, duodenum (small intestine_1), jejunum (small intestine_2 ~ small intestine_5), ileum (small intestine_6), cecum (large intestine_1), colon (large intestine_2 ~ large intestine_6), and rectum (large intestine_7).


The gut microbiome between locations within an individual was significantly different, while individual differences at the same locations of the GI tract were not as significant. Fecal microbiome was more closely related to the gut microbiome in large intestine than stomach or small intestine.

Intestinal bacteria in terms of both species number and their prevalence were dramatically increased as intestinal matter transited from the stomach to the large intestine. Cooccurrence network analysis showed the gradual adaptation of intestinal microbiota from stomach to large intestine:

  • At the same time, the highly dense and diverse bacteria in the large intestine were closely related to each other.
  • Fecal microbiome did not represent any microbiome at the 14 locations.

This work demonstrated that the fecal microbiome does not represent the overall composition of the gut microbiome. Despite significant roles of gut microbiome in various phenotypes and diseases of its host, causative microbes for such characteristics identified by one research fail to be reproduced in others.

Since fecal microbiome is a result of the gut microbiome rather than the representative microbiome of the GI tract of the host, there is a limitation in identifying causative intestinal microbes related to these phenotypes and diseases by studying fecal microbiome. It seems urgent to develop new methods for gut microbiome analysis.” “Fecal Microbiome Does Not Represent Whole Gut Microbiome”

This study showed that pig stomach and small intestine microbiota had few associations with fecal microbiota samples. Part 1 showed that only 6% of large intestine microbiota genes producing a secondary metabolite were found in human fecal samples.

What’s the point of poop microbiota studies when those microbiota don’t fairly represent ANY preceding gut microbiota, either overall or in actionable stages?

I don’t endorse this study’s Conclusions section suggestions of “endoscopic methods” because it ignores iatrogenic injuries and deaths. I’ll continue to give my trillion+ microbiota partners what they need, and expect reciprocity.


Measuring gut microbiota, Part 1

A 2023 paper combined results of two clinical trials focused on large intestine microbiota:

“Our current understanding of the gut microbiome places it at the center of multiple physiological processes, and establishes its relevance to many facets of health and disease. Microbiome databases are based upon stool samples or invasively-acquired colon samples obtained during procedures such as colonoscopy.

We present data from two prospective clinical studies describing significant differences between the stool microbiome and inner-colonic microbiome collected during FDA-cleared defecation-inducing, gravity-fed, and high-volume colonic lavage. We examined several microbiome characteristics, including microbial diversity, community differential abundance, and composition of biosynthetic gene clusters (BGCs).

BGCs are locally clustered groups of two or more genes that encode a biosynthetic pathway that produces a secondary metabolite:

  • 6% of identified BGCs were common to stool and pooled inner-colonic effluent samples, 25% were expressed only in stool, and 69% were unique to effluent samples.
  • When effluent-specific BGCs were divided according to colon areas, 25% were found in Effluent-1 (left descending colon), 21% in Effluent-2 (transverse colon), and 11% in Effluent-3 (right ascending colon).


Taxonomic and phylogenetic differences between inner-colonic effluent and stool samples increased gradually when approaching the proximal colon and small intestine:

  • Comparing the left colon to stool showed that 22 species were significantly enriched while only five species were significantly more abundant in stool.
  • A comparison between the transverse colon and stool revealed 76 species that were significantly more differentially abundant, while stool had 10 differentially abundant species.
  • The most significant differentially abundant species were found by comparing the right colon (closest to the small intestine) to stool, with 96 species differently enriched while stool had 20 species significantly enriched.

Individuals are far more distinct in their inner-colonic microbial community than in their stool samples. Microbiota are relatively similar across patients when examining stool samples, while expression of rare microbial strains is more specific to each individual.

Analyzing both stool and inner-colonic effluents can provide more information on the gut microbiome.” “The gut microbiome–Does stool represent right?”


Physical fitness and epigenetic clocks

This 2023 human study of 144 men average age 68 investigated relationships among physical fitness measurements and three epigenetic clocks:

“We investigated relationships between physical fitness and age-adjusted values from residuals of the regression of DNAm aging clocks to chronological age (DNAmAgeAcceleration: DNAmAgeAccel) and attempted to determine the relative contribution of physical fitness variables to DNAmAgeAccel in the presence of other lifestyle factors.

  • Volume of oxygen (VO2/kg) at ventilatory threshold and at Peak, fat free mass, calf circumference, serum HDL-C, daily intake of carbohydrates, iron, copper, vitamin C, and β-carotene were negatively related with DNAmAgeAccel.
  • Body fat, visceral fat area, and serum TG were positively related to DNAmAgeAccel.

figure 4

Frequent alcohol consumption and past- and current-smoking status were associated with accelerated DNAmAgeAccel, while a morning lifestyle was associated with deceleration of it. Multiple regression analysis suggested that – rather than physical fitness – serum triglycerides, carbohydrate intake, and smoking status were significantly associated with DNAmAgeAccel.

In conclusion, the contribution of cardiorespiratory fitness to DNAmAgeAccel was relatively low compared to lifestyle factors such as smoking. However, this study reveals a negative relationship between cardiorespiratory fitness and DNAmAgeAccel in older men.” “Associations between cardiorespiratory fitness and lifestyle-related factors with DNA methylation-based aging clocks in older men: WASEDA’S Health Study”


Remembering life before birth

This 2023 primate study investigated the body’s capability to remember prenatal experiences influencing later life:

“Maternal stressors and other environmental factors affect the developing embryo and fetus in ways that lead to increased susceptibility for chronic disease in later life. Developmental programming of chronic low-grade inflammation plays an important role in onset and progression of these diseases.

Establishing innate immune cell memory involves increased glycolysis, reduced oxidative phosphorylation, and expression of transcription factors which prime for pro-inflammatory activity. This memory relies on propagation of epigenetic modifications that develop in hematopoietic stem and progenitor cells (HSPCs), which can be passed on to progeny immune cells (i.e., macrophages).

These changes persist with altered epigenetic regulation for years after weaning – even when offspring are fed a conventional diet – predisposing offspring to inflammatory disease across their lifespans.

cell memory

Several factors may initiate metabolomic reprogramming in fetal HSPCs:

  • We found increased chromatin accessibility of gene regulatory regions and RNA signatures supporting activation of factors with a major role in regulating macrophage inflammatory activation, including FOS/JUN, NF-κB, C/EBPβ, and STAT6.
  • Our prior work demonstrated a persistently altered histone code in liver tissue from juvenile animals.
  • Maternal diet-supplied lipids, including oleic acid, in hematopoietic tissues may play an important role in priming inflammation and metabolism in fetal HSPCs and bone marrow-derived macrophages with postnatal persistence.

Striking changes in fetal bone marrow and liver HSPCs observed here suggest that the primary driver for developmental programming of inflammation takes place in utero. However, we cannot rule out that exposure to maternal diet during lactation postnatally triggers shifts in microbiome composition or function contributing to inflammation.

Components of maternal diet, rather than maternal obesity per se, are a modifiable risk factor with potential to alter developmental programming of offspring immune systems.” “Maternal diet alters long-term innate immune cell memory in fetal and juvenile hematopoietic stem and progenitor cells in nonhuman primate offspring”

And there are other ways we remember everything that happened then and along the way. Big clues are in our out-of-context responses to present day events.


Week 148 of Changing to a youthful phenotype with sprouts

Ending the week with a thorough 2023 study of microwaving broccoli in a bag:

“Appropriate processing and cooking technologies can effectively improve the content of bioactive compounds in vegetables. Effects of microwave bag cooking on broccoli floret quality attributes, glucosinolates (GLSs) content and hydrolysate production were investigated in this study.

Microwave bag cooking preserved the color of florets, enhanced total phenolic and flavonoid content, as well as total chlorophyll and ascorbic acid content. The majority of microorganisms were inactivated. Floret structure was greatly altered, enhancing antioxidant capacity and promoting release of GLSs and myrosinase activity.

Fresh broccoli (Brassica oleracea L. var. italica) was purchased from a local market. Broccoli balls with uniform size, no pests and no mechanical damage were selected for the experiment. Broccoli was washed with deionized water and dried naturally before being cut at about 1 cm below the flower head. The microwave bag was filled with 25 g florets and sealed with a heat sealer.

To the best of our knowledge, microwave bag cooking was evaluated for the first time to explore effects on sulforaphane (SFN) and indole-3-carbinol (I3C) content. Microwave bag cooking at 400 W for 10 s resulted in the highest SFN content (870.18 ± 19.14 μg/g), which was about 3.99 times that of untreated florets.

sfn content

Microwave bag cooking at 800 W for 10 s resulted in the highest I3C content, which was 6.16 times that of untreated florets.

i3c content

Our findings demonstrated that I3C in supplements or vegetables also degraded quickly under various processing conditions, such as thermal processing, and that DIM and LTr1 were not only produced in acidic conditions. This filled a gap in the literature regarding effects of vegetable processing, particularly thermal treatment, on content of glucobrassicin degradation products. In brief, under suitable conditions of microwave bag cooking, content of indole hydrolyzate I3C can be significantly increased, whereas content of dimerization and trimerization products did not change as significantly as I3C.

This work demonstrated that microwave bag cooking was a quick and easy cooking method that could preserve potential health benefits of broccoli florets while also satisfying the needs of modern consumers.” “Microwave bag cooking affects the quality, glucosinolates content and hydrolysate production of broccoli florets” (not freely available) Thanks to Professor Lei Zheng for providing a copy.

Can’t replicate this study’s cooking method completely. Ziploc bags are microwavable but a little different than heat-sealed bags. I also grow a broccoli / red cabbage / mustard sprout mix.

Using 25 grams of the mix and 40% power on my 1000W microwave for 10 seconds produced a sharper taste than did the method I’ve used. Scooping the mix out of a quart bag was messy.

I put the next 25 grams on a microwavable plate that snugly fit into a sealed bag. 80% power on a 1000W microwave for 10 seconds definitely tastes more cooked.


I’ll alternate between 400W and 800W for a while to see which one I prefer. It’s as quick and easy as claimed.


Environmental signaling rescues aging muscle stem cells

This 2023 rodent study applied An environmental signaling paradigm of aging concepts to muscle stem cells:

“The stem cell niche environment represents an important therapeutic target to enhance tissue regeneration in aging. We decoupled age-related cell-intrinsic effects, niche-mediated cell-extrinsic effects, and changes in population dynamics of muscle stem cells (MuSCs) and two key muscle-resident cells in young and aged mice.

in vivo model

We showed that:

  1. Age-related reduction in MuSCs is not stochastic.
  2. Despite differences in transcriptomes of MuSC clusters, the effect of age on gene expression is largely uniform, suggesting that the niche environment has a fundamental role in age-related changes in MuSC gene expression.
  3. A significant fraction of changes in the transcriptome of aging MuSCs can be reversed by exposure to the young muscle environment, i.e. are niche-responsive. Given the high percentage [46.6% at a stringent cutoff of s-value < 0.05] of reversibility in gene expression, our findings indicate that age-related changes in the niche are principal drivers of resulting alterations in the MuSC transcriptome.
  4. Aging is correlated with changes at the level of chromatin accessibility and DNA methylation in MuSCs.

Plasticity of the MuSC transcriptome suggests that modulating the niche environment can be a powerful tool to restore stem cell-mediated endogenous muscle regeneration in aging. Consequently, as opposed to focusing solely on MuSCs themselves to mitigate effects of aging on MuSCs, bioengineering of the niche in its entirety may be a viable therapeutic option.” “Transcriptional reprogramming of skeletal muscle stem cells by the niche environment”

This study destroyed extremely well-funded directed research efforts that detract from science, especially those promoting irreversibility of epigenetic changes (but: Rockefeller) and randomness of pro-aging programming (but: Harvard).

These researchers showed they could do more with their ideas and careers than maintain an outdated and easily disproved status quo.

Eat broccoli sprouts to epigenetically regulate histones

Five papers on beneficial effects from sulforaphane inhibiting histone deacetylases (HDACs), starting with a 2022 rodent cell study:

“Sulforaphane (SFN) has tissue specificity for subtypes of HDACs that are downregulated. For example:

  • In breast cancer cells, HDAC1-3 are inhibited by SFN to induce cell apoptosis;
  • In skin cells, HDAC1-4 are regulated by SFN [anti-skin cancer]; and
  • In the cochlea, SFN inhibits HDAC2, 4, and 5 [attenuates hearing loss].

In the present study, SFN significantly inhibited HDAC2, 3, and 5 expression and HDACs activity in cardiomyocytes, thereby increasing H3 acetylation levels in the Nrf2 promoter and upregulating Nrf2 expression. Mechanism by which SFN prevents Ang II-induced cardiomyocyte apoptosis:

  • Ang II activates oxidative stress by increasing ROS leading to inflammation, oxidative stress and fibrosis in cardiomyocytes.
  • SFN prevents Ang II-induced cardiomyocyte apoptosis by inhibiting HDACs to activate Nrf2 and downstream antioxidant genes.


SFN activates Nrf2 by inhibiting HDACs expression and activation.” “Sulforaphane inhibits angiotensin II-induced cardiomyocyte apoptosis by acetylation modification of Nrf2”

A 2021 rodent study found:

“SFN significantly attenuated diabetes-induced renal fibrosis in vivo. SFN inhibited diabetes-induced increase in HDAC2 activity.

Bone morphologic protein 7 (BMP-7) has been shown to reduce renal fibrosis induced by transforming growth factor-beta1. SFN protects against diabetes-induced renal fibrosis through epigenetic up-regulation of BMP-7.”

dmj-2020-0168f7 “Sulforaphane Ameliorates Diabetes-Induced Renal Fibrosis through Epigenetic Up-Regulation of BMP-7”

A 2019 human osteosarcoma cell study found:

“SFN inhibits mTOR in a concentration- and time-dependent manner. This inhibition occurs in the presence or in the absence of NRF2.

SFN inhibits HDAC6 and decreases catalytic activity of AKT, which partially explains the mechanism by which SFN inhibits mTOR.” “The isothiocyanate sulforaphane inhibits mTOR in an NRF2-independent manner”

A 2022 review cited a 2018 cell study:

“HDAC expression and activity are dysregulated in various diseases including asthma, chronic obstructive pulmonary disease, cancer, cardiac hypertrophy, and neurodegenerative and psychological disorders. HDAC inhibitors could be a potential therapeutic target for many diseases.

In hypertension, aortic stiffness is usually increased and vascular smooth muscle cells (VSMCs) contribute to vascular stiffness. We used VSMCs to test the degree of acetylation of histones in this study.

Sulforaphane weakly inhibited HDAC2 and effectively inhibited HDAC9.” “Zinc-dependent histone deacetylases: Potential therapeutic targets for arterial hypertension” “Inhibition of class IIa histone deacetylase activity by gallic acid, sulforaphane, TMP269, and panobinostat” (not freely available)


Measuring epigenetic DNA causes

This 2022 human cell study investigated DNA methylation and aging:

“Models based on DNA methylation can be used to predict the age of biological samples, but their interpretability is limited due to the lack of causal inferences. Neither existing epigenetic clocks nor DNA methylation changes are enriched in causal CpG sites. Causal CpGs include similar numbers of sites that contribute to aging and protect against it, yet their combined contribution negatively affects age-related traits.

One general approach for developing anti-aging interventions is to identify molecular changes during aging and use these changes as targets to modulate the aging process. A similar idea has also been applied to evaluate potential longevity interventions. However, this logic is intrinsically flawed, as correlation does not imply causation, and age-related changes are not necessarily causal to age-associated declines.

We developed a framework for integrating causal knowledge into epigenetic clock models and constructed DamAge and AdaptAge that measure age-related damaging and adaptive changes, respectively. DamAge acceleration is associated with various adverse conditions (e.g., mortality risk), whereas AdaptAge acceleration is related to beneficial adaptations.

causality clocks

We found that transcription factor (TF)-binding sites of BRD4 and CREB1 are enriched with CpG sites whose methylation levels promote healthy longevity, and TF-binding sites for HDAC1 are enriched with CpG sites whose methylation levels decrease healthy longevity.

  • BRD4 contributes to cell senescence and promotes inflammation, and higher DNA methylation at BRD4 binding sites may inhibit the downstream effects of BRD4 and promote healthy longevity.
  • CREB1 is related to type II diabetes and neurodegeneration, and mediates the effect of calorie restriction. Our data suggest that higher methylation at CREB1-binding sites may support its longevity effects.
  • HDAC1 is a histone deacetylase, and its activity increases with aging and may promote age-related phenotypes. Increased DNA methylation at HDAC1 binding sites may causally inhibit healthy longevity.

Our causality-informed clock models provide novel insights into the aging mechanisms and testing interventions that delay aging and reverse biological age.” “Causal Epigenetic Age Uncouples Damage and Adaptation”


Minds of their own

It’s the weekend, so it’s time for: Running errands? Watching sports? Other conditioned behavior?

Or maybe broadening our cognitive ability with Dr. Michael Levin’s follow-ups to his 2021 Basal cognition paper and 2020 Electroceuticals presentation with a 2022 paper and presentation starting around the 13:30 mark:

Michael Levin - Cell Intelligence in Physiological and Morphological Spaces

“A homeostatic feedback is usually thought of as a single variable such as temperature or pH. The set point has been found to be a large-scale geometry, a descriptor of a complex data structure.”

His 2022 paper Technological Approach to Mind Everywhere: An Experimentally-Grounded Framework for Understanding Diverse Bodies and Minds:

“It is proposed that the traditional problem-solving behavior we see in standard animals in 3D space is just a variant of evolutionarily more ancient capacity to solve problems in metabolic, physiological, transcriptional, and morphogenetic spaces (as one possible sequential timeline along which evolution pivoted some of the same strategies to solve problems in new spaces).

Developmental bioelectricity works alongside other modalities such as gene-regulatory networks, biomechanics, and biochemical systems. Developmental bioelectricity provides a bridge between the early problem-solving of body anatomy and the more recent complexity of behavioral sophistication via brains.

This unification of two disciplines suggests a number of hypotheses about the evolutionary path that pivoted morphogenetic control mechanisms into cognitive capacities of behavior, and sheds light on how Selves arise and expand.

While being very careful with powerful advances, it must also be kept in mind that existing balance was not achieved by optimizing happiness or any other quality commensurate with modern values. It is the result of dynamical systems properties shaped by meanderings of the evolutionary process and the harsh process of selection for survival capacity.”


The goddess of rainbows

Two 2022 papers, starting with a review of irisin:

“This article is an overview of irisin generation, secretion, and tissue distribution. Its targeting of tissues or organs for prevention and treatment of chronic diseases is systematically summarized, with discussion of underlying molecular mechanisms.

Irisin is an exercise-induced myokine expressed as a bioactive peptide in multiple tissues and organs. Exercise and cold exposure are major inducers for its secretion.

Mechanistic studies confirm that irisin is closely correlated with lipid metabolism, insulin resistance, inflammation, ROS, endocrine, neurotrophic factors, cell regeneration and repairing, and central nervous system regulation. Irisin decreases with age, and is closely associated with a wide range of aging-related diseases.

A number of studies in elderly humans and animal models have shown that exercise can promote the body’s circulation and increase irisin levels in some tissues and organs. Resistance, aerobic, or combined exercise seem to play a positive role. However, exercise could not change serum irisin in some reported studies.

irisin human studies

There are large individual differences in exercise training in the elderly population. Since the half-life of irisin in the body is less than 1 h, it is necessary to pay attention to the time of blood sampling after a single exercise intervention. Some factors that impede detection of irisin levels in vivo include the half-life of irisin protein, sampling time, different tissues, and different health statuses before and after intervention.

It is worth noting that high-intensity exercise shows higher irisin levels even with the same energy expenditure during exercise. Precision studies of irisin in elderly subjects following exercise intervention need to be further clarified.” “Irisin, An Exercise-induced Bioactive Peptide Beneficial for Health Promotion During Aging Process” (not freely available) Thanks to Dr. Ning Chen for providing a copy.

A second paper was a human study too recent to be cited by the first paper. I’ll highlight its irisin findings:

“We investigated the complex relationship among DNAm based biomarkers of aging, including DNAmFitAge, a variety of physiological functioning variables, blood serum measures including cholesterol, irisin level, and redox balance, and the microbiome on 303 healthy individuals aged between 33 and 88 years with a diverse level of physical fitness. Regular exercise was associated with younger biological age, better memory, and more protective blood serum levels.

Our research intends to show that regular physical exercise is related to microbiota and methylation differences which are both beneficial to aging and measurable. Our research provides the first investigation between microbiome derived metabolic pathways and DNAm based aging biomarkers.

Irisin levels decrease with age (0.23 average decrease for every 1 year older). We found age-related decreases in irisin levels were attenuated by exercise training. The link between irisin to GrimAge Acceleration and FitAge Acceleration is a novel observation.

HDL is positively associated with irisin. HDL and irisin have complex roles in physiology, and the positive relationship we observe between physical exercise and HDL and irisin align with protective effects seen between HDL and irisin with glucose homeostasis.

This work further supports the biological importance of irisin to the aging process. It is possible our research motivates interventions to boost irisin, like through physical exercise, as possible anti-aging therapies.” “DNA methylation clock DNAmFitAge shows regular exercise is associated with slower aging and systemic adaptation


Eat broccoli sprouts for your gut

Two 2022 papers, starting with a review of sulforaphane’s effects on intestinal inflammation:

“This review summarizes characteristics of intestinal inflammation, the anti-inflammatory mechanism of sulforaphane (SFN) and its various protective effects on intestinal inflammation, and possible future applications of SFN for promoting intestinal health.

SFN is an effective agonist of Nrf2, and it is also able to inhibit expression of inflammation-related genes by activating Nrf2. This kind of anti-inflammatory mechanism has already been confirmed in treatment of intestinal mucositis using SFN.

sulforaphane and gut inflammation

The main absorption site of SFN after oral administration is the small intestine, and its achievable dose for the hind intestine may be lower than the expected dose. Although absorbed SFN can reach the large intestine through intestinal blood and other transportation routes, its therapeutic effect on target tissues may not be as efficient as it would be when the expected dose is directly absorbed by hindgut cells.

Considering that there are several predisposing factors that lead to intestinal inflammation, more research on the effect of SFN on intestinal inflammation with different causes and characteristics should be carried out. Appropriate carriers should be selected according to the onset site and related physiological environment, and a scientific and effective intestinal targeted delivery system for SFN needs to be developed.” “The functional role of sulforaphane in intestinal inflammation: a review” (not freely available). Thanks to Professor Lei Zheng for providing a copy.

Reference 89 – Sulforaphane Normalizes Intestinal Flora and Enhances Gut Barrier in Mice with BBN-Induced Bladder Cancer (not freely available) – in the above graphic was cited for:

“The effect of SFN intervention on intestinal injury in mice with bladder cancer was investigated. It was found that SFN significantly reduced tissue damage in the colon and cecum of mice and normalized the imbalance in intestinal flora caused by BBN, which manifested as an increase in Bacteroides fragilis and Clostridium cluster 1, thus promoting SCFA production.

SFN administration upregulated expression of tight junction proteins including ZO-1, occludin, claudin-1 and glucagon-like peptide 2 (GLP2) to repair damage of mucosal epithelium of the colon and caecum, while reducing release of IL-6 and the secreted immunoglobulin A (SIgA). This study showed for the first time SFN’s alleviating effect on intestinal inflammation may be produced by regulating intestinal flora structure, suggesting that the protective effect of SFN on intestinal health could be multidirectional.”

That study’s 2022 follow-on rodent study also used oral sulforaphane doses:

“This study was undertaken to assess the potential efficacy of SFN in ameliorating dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice and to elucidate underlying mechanisms.

Male C57BL/6 mice were treated with various doses of SFN (2.5, 5, 10, and 20 mg/kg body weight). In DSS colitis mice, the hallmarks of disease observed as shortened colon lengths, increased disease activity index scores and pathological damage, higher proinflammatory cytokines and decreased expression of tight junction proteins, were alleviated by SFN treatment.

  • 5, 10, and 20 mg/kg/day of SFN treatment significantly ameliorated inflammatory damage in mice colon tissue when compared to the colitis group.
  • 5, 10, and 20 mg/kg/day of SFN remarkably mitigated morphological alterations and protected colonic tissue integrity.
  • Nrf2 expression was increased significantly by 5, 10, and 20 mg/kg/day of SFN treatment.
  • SFN partially restored perturbed gut microbiota composition, and increased production of volatile fatty acids (especially caproic acid) induced by DSS administration.
  • The contents of butyric acid, iso-butyric acid, valeric acid, and iso-valeric acid were all decreased in DSS-induced colitis mice and in 2.5 mg/kg/day of the SFN treatment group, whereas this decreased tendency was reversed by 10 and 20 mg/kg/day of SFN.

A proposed mechanism by which SFN protects against colitis:


Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), Signal Transducer and Activator of Transcription 3 (STAT3), and Phase II enzyme UDP-glucuronosyltransferase (UGT) were involved in the protective effect of SFN against DSS-induced colitis.

Nrf2 activation followed by STAT3 signaling pathway play a pivotal role in the protective effect of SFN on colitis. SFN can be considered a potential candidate in the treatment of IBD.” “The Protective Effect of Sulforaphane on Dextran Sulfate Sodium-Induced Colitis Depends on Gut Microbial and Nrf2-Related Mechanism”

A human equivalent dose of the second paper’s oral dose of 20 mg sulforaphane / kg body weight is (.081 x 20 mg) x 70 kg = 113 mg. Per Estimating daily consumption of broccoli sprout compounds, I ate about half that every day by microwaving 3-day-old broccoli sprouts through Week 56, when I cut back to about 35 mg a day. I dialed that back in Week 87 to about 17 mg a day (100 μmol), which is used in a plethora of studies.

I’ve never had ulcerative colitis or inflammatory bowel disease. If I would be diagnosed with either, it would take about five minutes to get back to this study’s equivalent of 10 mg / kg body weight with broccoli seeds and sprouts.

Doubling that to 20 mg may involve taking supplements, though. Haven’t checked for commercial availability lately, but I’ve read a dozen or so studies on encapsulating sulforaphane so that it could reach the colon.


Selecting broccoli varieties

This 2022 study evaluated 14 broccoli varieties grown in the same conditions for their floret compounds:

“Glucosinolate (GSL) profile and content in 11 inbred broccoli lines and three commercial cultivars were analyzed. Hydrolysate content, myrosinase activity, and nitrile formation rate were also determined.

Sulforaphane – an isothiocyanate (ITC) hydrolysate of glucoraphanin – content showed relatively higher value in the following order: 5404 > 5410 > 5407 > 5411, although glucoraphanin content was lower in those lines:


No significant relationship was found between myrosinase activity and total hydrolysate content, except in line 5310, which had the lowest myrosinase activity and the lowest total hydrolysate content. There was no significant correlation between myrosinase activities and sulforaphane.

We found a clear difference in selecting functional broccoli by considering only the GSL content or hydrolysates.

  • Even if total GSL content and individual GSL content were high, ITC content could not be produced at a high level.
  • When GSL content is high, if nitrile formation rate was also high, more nitrile than ITC would be produced.

Low nitrile formation rate and higher hydrolysate content should be considered when selecting functional broccoli lines with high GSL content.” “Selection of broccoli (Brassica oleracea var. italica) on composition and content of glucosinolates and hydrolysates”

As 3-day-old broccoli sprouts have the optimal yields, Lab analyses of broccoli sprout compounds, Tailoring measurements for broccoli sprouts, and this study found, there weren’t many potential health benefits based solely on broccoli varieties’ glucoraphanin contents. But genotypes had a greater effect than did environmental influences, and seed / sprout / stalk / floret beneficial contents differed.

There are opportunities for vendors to showcase healthier broccoli products. Growing, harvesting, and storage conditions will make that expensive to test and certify, though.

As A follow-on study to 3-day-old broccoli sprouts have the optimal yields, Enhancing sulforaphane content, and Microwave broccoli to increase sulforaphane levels showed, there are ways to improve myrosinase activity and isothiocyanate yield. I do these easy actions every day while growing 3-day-old sprouts from unknown broccoli varieties. Waiting for evidence to compel changing that.

Strange birds


Sulforaphane vs. too much oxygen

This 2021 rodent study investigated perinatal effects of hyperoxia and sulforaphane:

“We demonstrated that early-life oxidant-induced acute lung injury had significant consequences later in life on NRF2-dependent respiratory syncytial virus (RSV) susceptibility in mice. We also determined that increased antioxidant conditions in utero potentially contribute to a decreased risk of postnatal airway disease as we found that prenatal antioxidant sulforaphane (SFN) protected developing lungs from bronchopulmonary dysplasia (BPD)-like oxidative pathogenesis in mice.

Unexpectedly, our results indicated that prenatal SFN-mediated postnatal protection against BPD-like phenotypes are not NRF2-dependent. Prenatal SFN markedly improved hyperoxia-caused severe BPD-like lung injury parameters in Nrf2−/− pups while we observed relatively marginal protection by in utero SFN in hyperoxia-resistant Nrf2+/+ pups.

SFN is a strong NRF2 and ARE gene inducer for cytoprotection by NRF2 stabilization. However, SFN also acts through other mechanisms, including NF-κB inhibition, MAPK activation, and histone deacetylase inhibition for anti-inflammation, chemoprevention, apoptosis, and autophagy.

Our study provided new insights into infant oxidant lung injury severity influence on persistence of pulmonary morbidity and therapeutic intervention for NRF2 agonists. Our results also provided justification for further studies on feto–placental barrier crossing of SFN metabolites and SFN-triggered molecular and epigenetic aspects of maternal cues for barrier and fetal lung signaling.” “Murine Neonatal Oxidant Lung Injury: NRF2-Dependent Predisposition to Adulthood Respiratory Viral Infection and Protection by Maternal Antioxidant”

This study’s oral human-equivalent dose for treatment dams was 9 mg sulforaphane (1.67 mg x .081 x 70 kg) every other day during the last half of pregnancy. A small dose per How much sulforaphane is suitable for healthy people?

“The daily SFN dose found to achieve beneficial outcomes in most of the available clinical trials is around 20-40 mg.”


Eat broccoli sprouts to prevent radiation damage

This 2021 rodent study investigated effects of sulforaphane on skin damage from irradiation:

“Radiotherapy is currently the main treatment for various cancers. We observed the protective effect of sulforaphane (SFN) on radiation-induced skin injury (RISI), including oxidative stress and inflammatory response indexes, and Nrf2 expression with its downstream antioxidant genes:

  • SFN prevented DNA damage caused by radiation.
  • SFN prevented and treated radiation-induced skin inflammation.
  • SFN prevented radiation-induced oxidative stress in skin.
  • Activation of Nrf2 and expressions of its downstream genes in skin induced by SFN.

Nrf2 downstream antioxidant genes induced by SFN

Mice were randomly assigned to one of four groups (n = 8), including control group (CON), SFN group, irradiation (IR) group, and IR plus SFN (IR/SFN) group (* p < 0.05 vs. CON; & p < 0.05 vs. IR).

Our most innovative discovery was that SFN provided skin protection from IR. At present, there are a few drugs to treat RISI in clinical patients, but the effect is not very ideal, or some may cause certain side effects.

SFN extracted from natural broccoli has no toxicity and is easily accepted for usage in clinic. According to our findings, SFN will provide a new strategy for clinical treatment and prevention of RISI in the future.” “Sulforaphane-Mediated Nrf2 Activation Prevents Radiation-Induced Skin Injury through Inhibiting the Oxidative-Stress-Activated DNA Damage and NLRP3 Inflammasome”

This study’s findings probably also apply to less-severe skin damage caused by sun exposure.


Epigenetic clocks so far in 2021

2021’s busiest researcher took time out this month to update progress on epigenetic clocks:

Hallmarks of aging aren’t all associated with epigenetic aging.

epigenetic aging vs. hallmarks of aging

Interventions that increase cellular lifespan aren’t all associated with epigenetic aging.

epigenetic aging vs. cellular lifespan

Many of his authored or coauthored 2021 papers developed human / mammalian species relative-age epigenetic clocks.

epigenetic clock mammalian maximum lifespan

Relative-age epigenetic clocks better predict human results from animal testing.

pan-mammalian epigenetic clock

Previously curated papers that were mentioned or relevant included: