Sulforaphane clinical trials and COVID-19

A plethora of articles have been published this year on how researchers’ favorite topics can / may / should / could / will fix COVID-19. This one was different in that relevant clinical trials were both completed and already underway before a Madness of Crowds behavioral contagion infected us:

“It is crucial to understand the most appropriate context for introducing an anti-inflammatory therapy to complement an antiviral therapy. Such therapy must control inflammation without altering the ability of the host to mount an efficient adaptive immune response against the virus.

We propose that boosting endogenous cellular defenses by targeting the cytoprotective transcription factor Nrf2 (gene name NFE2L2) will promote the resolution of COVID-19 associated inflammation and also restore redox homeostasis and facilitate tissue repair.

The isothiocyanate sulforaphane (SFN) is the most potent naturally occurring NRF2 activator, with well-documented antioxidant and anti-inflammatory effects. The high bioavailability of SFN makes it an excellent candidate for alleviating excessive anti-inflammatory responses and protecting the lungs.

Even though Nrf2 is the primary mediator, additional factors contribute to the anti-inflammatory effects of SFN. SFN inhibits NF-κB, inhibitor of NF-κB kinase subunit β (IKKβ), and STAT3.

By regulating the endogenous cytoprotective systems, Nrf2 may have a more physiological role in achieving a balance between the beneficial and adverse effects of inflammation. Nrf2 inhibits IL-6 and IL-1β gene expression.

Antioxidant and cytoprotective effects of Nrf2 activation are long-lasting and persist for several days after inducer elimination. They are mediated by enzymes that, in contrast to small molecules, have long half-lives and are not consumed, and are instead regenerated during the reactions which they catalyze.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7359808/ “Can Activation of Nfr2 Be a Strategy against COVID-19?”


The paper also documented in vitro, animal, and non-clinical human Nrf2 activator studies relevant to causes and effects.

Sulforaphane and RNAs

This 2020 Texas review subject was long non-coding RNAs:

“We review the emerging significance of long non-coding RNAs (lncRNA) as downstream targets and upstream regulators of the Nrf2 signaling pathway, a critical mediator of diverse cellular processes linked to increased cell survival.

It is believed that more than 3% of human genes are regulated by the Nrf2/Keap1 pathway. In addition to the classical cytoprotective and oxidative stress response genes transactivated by Nrf2, emerging evidence suggests a role for non-coding transcript regulation at the level of noncoding RNAs, [which] far outnumber protein-coding genes in the human genome.

One important distinction between miRNAs and lncRNAs is that the latter are often species-specific, meaning that a human lncRNA typically cannot be studied in the mouse or rat, and vice versa.

Sulforaphane (SFN) acts via multiple mechanisms to modulate gene expression, including the induction of Nrf2-dependent signaling. In addition to the established canonical targets of Nrf2, such as NQO1 and HMOX1, SFN altered the expression of multiple lncRNAs.

Given that SFN induces NMRAL2P [a lncRNA pseudogene] and several other lncRNAs in colon cancer cells, further studies are warranted on their respective roles as upstream regulators and/or downstream targets of Nrf2 signaling.

Pharmacological modulation of Nrf2 is considered a viable strategy against chronic conditions that are accompanied by oxidative stress and inflammation:

  • DMF [dimethyl fumurate] is the most successful Nrf2 activator, FDA-approved in 2013 for the treatment of relapsing remitting multiple sclerosis. However, DMF causes leukopenia and other side-effects.
  • Bardoxolone cleared Phase II clinical trials for the treatment of advanced chronic kidney disease and type 2 diabetes mellitus, but was halted in Phase III trials due to cardiovascular concerns.
  • SFN is relatively unstable at room temperature.

We used reported bioinformatics approaches to search for putative ARE [antioxidant response element] sequences among the entire set of 16,000+ annotated human lncRNAs. 13,285 promoter regions contained one or more potential binding sites for Nrf2.”

https://www.sciencedirect.com/science/article/pii/S0304383520303670 “Emerging crosstalk between long non-coding RNAs and Nrf2 signaling”


This study hyped lncRNAs in that only 7 have been validated as Nrf2 targets, and 8 validated as Nrf2 regulators. For regulators, “protein and/or miRNA interacting partners are yet to be fully corroborated” as well.

Also, there’s no need for a “SFN is relatively unstable at room temperature” problem. Just create sulforaphane right before consuming it.

Twice a day I microwave an average 65.5 grams of 3-day-old broccoli sprouts immersed in 100 ml water with a 1000W microwave on full power for 35 seconds to ≤ 60°C. After microwaving I transfer broccoli sprouts to a strainer, and wait five minutes to allow further myrosinase hydrolization of glucoraphanin and other glucosinolates into sulforaphane and other healthy compounds.

Reprogram inflammation with β-glucan

This 2020 French human cell study found:

“Exposure of mononuclear phagocytes to β-glucan contributes to the induction of innate immune memory, which is associated with long-term epigenetic, metabolic, and functional reprogramming. We investigated how preincubation of human monocytes with particulate β-glucan affects the biological response of macrophages following NLRP3 inflammasome activation.

Upon infection or cellular damage, NLRP3 assembles into a multiprotein inflammasome complex leading to the release of IL-1β. However, NLRP3 inflammasome activity can also be detrimental to the host, and its aberrant chronic activation is associated with severe pathologies.

β-Glucan is a safe molecule present in food products and already widely used in food supplementation. Although β-glucan–induced innate memory is associated with a nonspecific protective effect against infections, the role of this functional reprogramming in autoinflammatory disorders is unknown.

Because of the administration frequency and conservation needs, IL-1β–targeted therapy is invasive, complex, and also costly. In addition, IL-1β, an acute-phase protein, is crucial for effective immune responses to infection, and inhibitors targeting IL-1β may lead to unintended immunosuppressive effects in addition to preventing NLRP3 inflammasome activity in itself.

Targeting the origin of the disease, i.e., NLRP3, would represent the best therapeutic strategy. Most of these candidate drugs directly interact with NLRP3, but none seems to regulate the early activation events upstream of NLRP3 inflammasome assembly.

β-Glucan acted upstream of the NLRP3 inflammasome. β-glucan–induced innate immune memory represses IL-1β–mediated inflammation and support its potential clinical use in NLRP3-driven diseases.”

https://www.jci.org/articles/view/134778 “β-Glucan–induced reprogramming of human macrophages inhibits NLRP3 inflammasome activation in cryopyrinopathies”


This study came closer to addressing causes than others with:

“Targeting the origin of the disease would represent the best therapeutic strategy.”

It’s apparently too recent with a July 27th published date to make it onto https://www.betaglucan.org/i-p/, but earlier β-glucan inflammation studies may be found there.

Topical sulforaphane protects skin

This 2020 Rutgers rodent study explored topical application of sulforaphane to prevent UVB-induced skin carcinogenesis:

“We investigated the transcriptomic and DNA methylomic changes during tumor initiation, promotion, and progression and its impact and reversal by sulforaphane (SFN). The production of ROS and inflammation are closely linked to UVB-induced carcinogenesis. SFN protects skin cells from UVB-induced damage mainly through promoting anti-inflammatory, antioxidative and anticancer pathways.

We observed the changes after 2, 15 and 25 weeks of UVB exposure, which would represent the three different stages of skin cancer development. After 2 weeks of UVB exposure, we did not observe any obvious tumors in the UVB group. But after 15 weeks of UVB exposure, some obvious tumors were observed in the skin.

After 15 weeks of UVB treatment in epidermal tissue, the difference between the UVB group and the control group was significantly more than that between the SFN group versus the UVB group. SFN appears to have better cancer-protective effects in earlier time points (weeks 14 and 20) than later time point (week 24). At weeks 20, SFN had significantly fewer tumors with decreased total tumor volume and tumor number.

SFN plays a highly regulatory role in various signaling pathways during UVB irradiation. SFN impacts UVB-induced alterations of DNA methylation profiles, and importantly, SFN treatment attenuates some of these DNA methylation changes. We found a subset of genes associated with SFN treatment, and the relevant changes in gene expression may be driven by promoter CpG methylation status.”

https://cancerpreventionresearch.aacrjournals.org/content/13/6/551 “Epigenome, Transcriptome, and Protection by Sulforaphane at Different Stages of UVB-Induced Skin Carcinogenesis” (not freely available)


We’re getting closer to using epigenetic clocks in sulforaphane studies. This study ignored the 2018 A multi-tissue full lifespan epigenetic clock for mice in favor of their homegrown DNA methylation measurements.

A search of ClinicalTrials.gov didn’t turn up directly relevant human studies.

Eat sauerkraut today!

This 2017 Spanish article reviewed health benefits of sauerkraut:

“During cabbage shredding and fermentation, a disruption of cabbage cells occurs, and GLS [glucosinolates] are hydrolyzed by myrosinase enzyme to a variety of GLS breakdown products. In particular, glucobrassicin is hydrolyzed into indol-3-carbinol (I3C) by myrosinase.

As the pH decreases during cabbage fermentation, I3C reacts nonenzymatically with ascorbic acid to yield ascorbigen (ABG). Studies have shown that ABG is the main GLS breakdown compound in sauerkraut, and it is present at levels between 3 and 18 μmol/100 g fw.

The antioxidant activity observed for sauerkraut in all studies was higher than that observed in raw cabbage.

It has been reported that doses between 53 and 150 μmol of ITCs [isothiocyanates] are enough to display anticarcinogenic effects. Taking into account that the content of ITCs in sauerkraut is in the range 22 μmol/100 g fw, it could be assumed that a weekly consumption of 200–250 g of sauerkraut would provide effective ITC doses to exert cancer chemopreventive effects.

Many studies reported that LAB [lactic acid bacteria] isolated from sauerkraut are potential probiotics.”

https://www.sciencedirect.com/science/article/pii/B9780128023099000248 “Sauerkraut: Production, Composition, and Health Benefits” (not freely available)


This introductory article presented interesting facts, but oversold sauerkraut. Dose and other conditional dependencies in order to achieve health and disease prevention benefits seemed to be beyond its scope.

A more considered view was offered in Fermented Food and Non-Communicable Chronic Diseases which referenced this article:

“Clinical data about the effects of sauerkraut on the human organism, health and disease are scarce. There is knowledge concerning particular compounds in sauerkraut and their impacts on diseases; however, a literature search revealed mostly cell line or rat experiments with very limited conclusions for humans.”


Earlier this month I started eating refrigerated sauerkraut twice a day with microwaved broccoli sprouts. I mix in three heaping teaspoons each time, and finish a 50 oz (1418 g) container in a week.

The mixture tastes better than just microwaved broccoli sprouts. It requires more chewing, which assists myrosinase hydrolization of broccoli sprout glucosinolates into sulforaphane and other healthy compounds.

Although sauerkraut isn’t a primary source, there may be beneficial amounts of probiotics etc. that increase what I get with broccoli sprouts and supplements.

I also started making my own sauerkraut using the commercial product’s juice as a starter. I add garlic but not salt. No results yet.

Transgenerational epigenetic inheritance of epimutations

My 600th curation is a 2020 rodent study from Dr. Michael Skinner’s labs at Washington State University:

“Numerous environmental toxicants have been shown to induce the epigenetic transgenerational inheritance of disease and phenotypic variation. Alterations in the germline epigenome are necessary to transmit transgenerational phenotypes.

In previous studies, the pesticide DDT and the agricultural fungicide vinclozolin were shown to promote the transgenerational inheritance of sperm differential DNA methylation regions, non-coding RNAs and histone retention, which are termed epimutations. The current study was designed to investigate the developmental origins of the transgenerational differential histone retention sites (called DHRs) during gametogenesis of the sperm.

In addition to alterations in sperm DNA methylation and ncRNA expression previously identified, the induction of DHRs in the later stages of spermatogenesis also occurs. This novel component of epigenetic programming during spermatogenesis can be environmentally altered and transmitted to subsequent generations.

While the DHR may be consistent and present between the stages of development, the histone modifications may be altered. Several of the core histone retention sites absent in the DHRs had altered histone methylation. This adds a level of complexity to the potential role of histone retention in that it may be not only the retention, but also the alterations in histone epigenetic modifications.

The DHRs had positional associations with genes and the major functional categories were signaling, metabolism and transcription.

In the event the embryo stem cell population has a modified epigenetics and corresponding transcriptome, then all somatic cells derived from the stem cell population will have an altered cascade of epigenetic and gene expression programming to result in adult differentiated cells with altered epigenetics and transcriptomes. Previous observations have demonstrated in older adult human males alterations in histone retention develop and are associated with infertility.

Similar observations have also been provided for the development of differential DNA methylation regions (DMRs) induced by environmental toxicants such as DDT and vinclozolin. Since DHRs have a similar developmental programming, other epigenetic processes such as ncRNA are also anticipated to be similar.”

https://www.sciencedirect.com/science/article/pii/S0012160620301834 “Developmental origins of transgenerational sperm histone retention following ancestral exposures”


This study, like its dozens of predecessors performed year after year by this research facility, provided evidence for mechanisms of epigenetic transgenerational inheritance. The studied F3 generation members were great-grand-offspring, the first generation to have no direct exposure to DDT and vinclozolin.

As pointed out in A compelling review of epigenetic transgenerational inheritance:

“During the 1950s, the entire North American population was exposed to high levels of the pesticide DDT, when the obesity rate was < 5% of the population. Three generations later, the obesity frequency in North America is now ~45% of the population.”

There are varieties of mischaracterizations and hand-waving denials of epigenetically-inherited diseases. People don’t want to hear about and read proof that something we did or experienced disfavored our children, who unwittingly passed resultant problems on to their children, and which furthered on to their children’s children.

Take responsibility for your one precious life – β glucan

From the main page of https://www.betaglucan.org/, a compilation for researchers:

“Beta Glucan extracted from yeast cell wall, can be a potent immune response potentiator and modulator. A common test to determine a glucan’s immune response potentiation effectiveness is the measure of the degree to which a glucan increases the nitric oxide burst, a pathogen killing agent.

Determinants of immune response activation and effectiveness are beta glucan source, processing, sizing and uniformity of beta glucan particles ingested. Particle size of 1-4 microns is optimum. Ingestion is optimized to prevent reaggregation.”


A sample of research:

“The tested (and suggested) daily dose remains in the range of 100–500 mg for stimulation of the immune system, whereas for a decrease in cholesterol levels a daily dose of 3 g is recommended.

Glucan supplementation prevents or even treats metabolic syndrome and decreases insulin resistance, dyslipidemia, and obesity. Glucan supplementation is a highly promising and inexpensive method of treatment for chronic respiratory problems.

Reactions known to be influenced by glucan are represented in white, reactions where glucan has no confirmed effects are shown in black.”

https://www.mdpi.com/1420-3049/24/7/1251/htm “Beta Glucan: Supplement or Drug? From Laboratory to Clinical Trials”


“Supplementation with glucan and vitamin D resulted in significant increase of vitamin D levels, improvements of HDL levels, and strong decrease of the total level of cholesterol.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5897984/ “Effects of β-glucan and Vitamin D Supplementation on Inflammatory Parameters in Patients with Diabetic Retinopathy”


“β-glucan inhibits tumor growth through induced systemic tumor-antigen specific T cell response, increased activity of T-cells in tumor, and decreased number of tumor-caused immunosuppressive cells. Sulforaphane inhibits CRC [colorectal cancer] carcinogenesis by modulating Nrf2 activity and inhibition of HDAC enzymes.

In a women’s health initiative prospective cohort during their 11.7-year follow up of dietary fiber and omega-3, -6 fatty acids, the results pointed out a reduced incidence of CRC for the association between a low dose of soluble fiber, a high dose of insoluble fiber, and a high dose of EPA and DHA.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6321468/ “Chemoprevention of Colorectal Cancer by Dietary Compounds”


I first curated the above review and graphic in Train your immune system every day! 12 days into a self-quarantine after coming back from Milano, Italy, Monday, February 24, 2020. There’s a substantial probability that my traveling companion and I were exposed to COVID-19.

Yet neither of us had any symptoms then or since. My β-glucan, Vitamin D3, and zinc amounts were the same as described in that post, in Take responsibility for your one precious life – Vitamin D3, and in Take responsibility for your one precious life – Zinc.

Take responsibility for your one precious life – Vitamin D3

Where to start among 6,489 studies and reviews published during the past five years, results from a PubMed search of “dihydroxyvitamin D3.” How about:

“Vitamin D plays a fundamental role in body calcium and phosphorous homeostasis, ensuring proper functioning of the skeletomuscular system. Pleiotropic activities include:

  • Anti-inflammatory and immunomodulatory properties (predominantly downregulation of adaptive and upregulation of innate immunity);
  • An important role in reproduction, pregnancy, placental functions and fetal and child development;
  • Important in neurodevelopment as well as in the functioning of the adult central and peripheral nervous system;
  • Regulation of global metabolic and endocrine homeostasis and the functions of different endocrine organs, as well as in the functioning of the cardiovascular system;
  • Inhibits malignant transformation, tumor progression and has anti-cancer properties on a variety of tumors;
  • Formation of the epidermal barrier and hair cycling; and
  • Ameliorating effects on skin cancer and on proliferative and inflammatory cutaneous diseases.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6342654/ “The serum vitamin D metabolome: What we know and what is still to discover”


Or maybe:

“A study in 6,275 American children and adolescents aged 1–21 years showed that 61% were 25-(OH)D3 insufficient and 9% deficient. In adults, up to 40% are 25-(OH)D3 insufficient and 6% deficient.

Once adequate vitamin D values are reached, to further preserve adequate vitamin D levels in adults, the IOM [Institute of Medicine] recommends a daily dose of 600 IU per day, while the Endocrine Society recommends a dose of 600–2000 IU per day (according to the amount of sunlight the individual is exposed to). There seems to be no additional health benefit in doses higher than 4000 IU/day.

Vitamin D supplementation was protective against acute respiratory tract infections in a 25-(OH)D3 deficient population, especially in those receiving daily or weekly supplementation. However, in children this protective effect could not be reproduced.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7281985/ “Vitamin D’s Effect on Immune Function”


Not to forget Advanced glycation end products alter steroidogenic gene expression by granulosa cells: an effect partially reversible by vitamin D:

“This study suggests that there is a relationship between AGEs (advanced glycation end products) and their receptors (RAGE and sRAGE) with vitamin D. Understanding the interaction between AGEs and vitamin D in ovarian physiology could lead to a more targeted therapy for the treatment of ovarian dysfunction.”


Or similarities to broccoli sprouts’ main effect of Nrf2 signaling pathway activation:

“1,25(OH)2D3 plays a role in delaying aging by upregulating Nrf2, inhibiting oxidative stress and DNA damage, inactivating p53‐p21 and p16‐Rb signaling pathways, and inhibiting cell senescence and SASP.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6516172/ “1,25‐Dihydroxyvitamin D exerts an antiaging role by activation of Nrf2‐antioxidant signaling and inactivation of p16/p53‐senescence signaling”


Why do we insist on giving ourselves non-communicable diseases?

I recently paid $22.53 after tax for a nearly two-year supply:

A better use of one’s money would be..?

My June 2020 serum 25-OH Vitamin D measurement was 76 on a scale of 0 to 100 from taking a total of 3,400 IU daily. It’s fat-soluble, so I take it along with 1 gram flax oil each time.

Take responsibility for your own one precious life.

Take responsibility for your one precious life – Zinc

This 2020 review highlighted earlier clinical data on zinc:

  • “Zinc is known to modulate antiviral and antibacterial immunity and regulate inflammatory response.
  • Zinc possesses anti-inflammatory activity by inhibiting NF-κB signaling and modulation of regulatory T-cell functions.
  • The most critical role of zinc is demonstrated for the immune system.
  • Zinc regulates proliferation, differentiation, maturation, and functioning of leukocytes and lymphocytes.

Alteration of zinc status significantly affects immune response resulting in increased susceptibility to inflammatory and infectious diseases including acquired immune deficiency syndrome, measles, malaria, tuberculosis, and pneumonia. Zinc status is associated with the prevalence of respiratory tract infections in children and adults.

In view of the high prevalence of zinc deficiency worldwide (up to 17%), its impact on population health is considered as a significant issue. Certain groups of people, including infants, especially preterm ones, and elderly, are considered to be at high risk of zinc deficiency and its adverse effects.

Zinc was shown to have a significant impact on viral infections through modulation of viral particle entry, fusion, replication, viral protein translation and further release for a number of viruses including those involved in respiratory system pathology. Increasing intracellular Zn levels through application of Zn ionophores significantly alters replication of picornavirus, the leading cause of common cold.

The results of systematic analysis confirmed the efficiency of intake of at least 75 mg/day Zn in reduction of pneumonia symptom duration but not severity, with the response being more pronounced in adults than in children.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7255455/ “Zinc and respiratory tract infections: Perspectives for COVID-19”


The review noted a 2014 rodent cell study which found:

“Labile zinc, a tiny fraction of total intracellular zinc that is loosely bound to proteins and easily interchangeable, modulates the activity of numerous signaling and metabolic pathways. Dietary plant polyphenols such as the flavonoids quercetin and epigallocatechin-gallate act as antioxidants and as signaling molecules. The activities of numerous enzymes that are targeted by polyphenols are dependent on zinc.

We have demonstrated the capacity of quercetin and epigallocatechin-gallate to rapidly increase labile zinc. The polyphenols transport zinc cations across the plasma membrane independently of plasma membrane zinc transporters.

The ionophore activity of dietary polyphenols may underlay the raising of labile zinc levels triggered in cells by polyphenols and thus many of their biological actions.”

https://pubs.acs.org/doi/10.1021/jf5014633 “Zinc Ionophore Activity of Quercetin and Epigallocatechin-gallate: From Hepa 1-6 Cells to a Liposome Model” (not freely available)


I get EGCG from drinking 4-5 cups of green tea every day, and 65 mg zinc from supplements. Microwave broccoli to increase flavonoid levels demonstrated 108.5% to 129.8% increases in quercetin and kaempferol levels from microwaving grocery-store broccoli. Microwaving 3-day-old broccoli sprouts may be expected to increase my worst-case calculation of daily 134 mg total flavonoids.

I’ve taken quercetin intermittently per Preliminary findings from a senolytics clinical trial. I’m changing that to take 100 mg quercetin daily.

Take responsibility for your own one precious life.

Autism biomarkers and sulforaphane

This 2020 US human study investigated autism improvements with sulforaphane:

“Autism Spectrum Disorder (ASD) is one of the most common neurodevelopmental disorders that, in the United States, is currently estimated to affect 1 out of 59 children who are 8 years old. Despite decades of research and advances in our knowledge of etiologies of ASD, treatments and biomarkers for ASD remain limited.

The primary diagnosis of ASD still relies on observational tools that are by nature subjective. There are currently no drugs approved to treat core symptoms of ASD, nor are there any studies using SF [sulforaphane] in genetic mouse models of ASD.

In our previous placebo-controlled, double-blinded, randomized clinical trial, daily administration of SF for 4-18 weeks substantially improved behavioral abnormalities of the majority of 26 young males with moderate to severe ASD without significant toxicity. The multi-functional phytochemical sulforaphane affects many biochemical abnormalities associated with ASD.

We investigated potential molecular markers from three ASD-associated physiological pathways that can be affected by sulforaphane:

  1. Redox metabolism / oxidative stress;
  2. Heat shock response; and
  3. Immune dysregulation / inflammation

in peripheral blood mononuclear cells (PBMCs) from healthy donors and patients with ASD.

Three representative Nrf2 [nuclear factor erythroid 2-related factor 2]-dependent enzymes:

  1. AKR1C1 [aldo-keto reductase family 1 member C1];
  2. NQO1 [dehydrogenase quinone 1]; and
  3. HO-1 [heme oxygenase]

were significantly induced by 6 h of 2 μM or 5 μM SF ex vivo treatments in PBMCs from healthy donors. This time point was chosen based on our earlier observations of kinetics of upregulation of Nrf2-dependent genes by SF, and was expected to capture increased mRNA production of both very fast (HO-1) and relatively slow (NQO1) responders.

There was no concentration-dependence in induction of any genes examined, with higher (5 μM) concentration of SF even showing a slightly diminished effect for induction of AKR1C1 and NQO1. Although this concentration is achievable in vivo, more typical peak concentrations of SF (and its metabolites) in human plasma are 1-2 μM.

SF ex vivo pre-treatment significantly decreased the LPS [lipopolysaccharides]-stimulated inflammatory gene (

  • COX-2,
  • TNF-α,
  • IL-6 and
  • IL-1β

) expression levels in PBMCs from healthy donors.

As a pilot study for a clinical trial of SF in children with ASD, we evaluated the same biomarkers from the ex vivo studies in 10 young males with ASD, 6-12 years of age, who received SF (in the form of a dietary supplement containing GR [glucoraphanin] and myrosinase), 2.2 μmol/kg/d for 14 days. Grouping by broad functionality (e.g. cytoprotective or pro-inflammatory), differences from baseline were highly significant.

asd gene expression

Individually none is sufficiently specific or sensitive, but when grouped by function as two panels, these biomarkers show promise for monitoring pharmacodynamic responses to sulforaphane in both healthy and autistic humans, and providing guidance for biomedical interventions. We conducted this study in the context of ASD, however our findings have broader implications and suggest that these biomarkers can be used in any study involving an intervention with SF.

Major signaling pathways for protective mechanisms against ASD by SF:

  • (a) Keap1/Nrf2/ARE pathway,
  • (b) NF-κB inflammatory pathway,
  • (c) Heat-shock responses.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7118069/ “Biomarker Exploration in Human Peripheral Blood Mononuclear Cells for Monitoring Sulforaphane Treatment Responses in Autism Spectrum Disorder”


This was a pilot study. Does sulforaphane treat autism? was its follow-on clinical trial.

Broccoli sprouts and sulforaphane aren’t panaceas. Their research is becoming more intensive and focused, though.

Microwave broccoli seeds to create sulforaphane

Two sulforaphane topics came up in discussions with my traveling companion. Our first was an inference:

  1. 3-day-old broccoli sprouts have the optimal yields found that broccoli sprout sulforaphane content (after processing for analysis) ranged from 46% to 97% of broccoli seeds.
  2. Microwave broccoli to increase sulforaphane levels found that microwaving broccoli florets to 60°C (140°F) increased the sulforaphane amount from .22 to 2.45 µmol / g (1,114%!!).
  3. Wouldn’t broccoli seeds’ sulforaphane be more than broccoli sprouts by microwaving seeds up to 60°C in the same amount of water?

The 3-day study broccoli sprout measurements were relative to each variety’s seeds:

“To be comparable, the content of these bioactive compounds from 100 fresh sprouts was divided by the weight (gram) of 100 seeds, and then this value was compared with their content from one gram seeds.”

Broccoli compounds are similar among broccoli florets, sprouts, and seeds. A major difference is that broccoli sprouts and seeds have no initial sulforaphane content because hydrolization hasn’t occurred yet. The above graphic’s seed and sprout sulforaphane content was created by processing for analysis.

I’ll reason that sulforaphane would be created by:

  • Microwaving one tablespoon of broccoli seeds with a 1000W microwave in 100 ml of distilled water for 30 seconds to ≤ 60°C; then
  • Straining out the water; then
  • Allowing further myrosinase hydrolization of glucoraphanin and other glucosinolates into sulforaphane and other healthy compounds.

Broccoli seeds are dry, and microwaving acts directly on a material’s water content. The 3-day study methods “immersed [broccoli seeds] in distilled water and soaked at 30°C for 2 h” to start germination. I’ll stipulate two hours as a minimum broccoli seed soaking time before microwaving.

I’ve tried microwaving broccoli seeds five times so far to see if they’re palatable. Seeds soaked for at least two hours then microwaved for 30 seconds swell to almost twice their dry size. They’re easier to strain, chew thoroughly to ensure hydrolization, and swallow.

The 3-day study also found “total phenolic and flavonoid contents in sprouts were 1.12 to 3.58 times higher than seeds.” I won’t stop eating broccoli sprouts, but sometimes it may be expedient to reduce a 72-hour preparation time to 2 hours and still benefit from sulforaphane and other healthy broccoli compounds.

Let’s use Estimating daily consumption of broccoli sprout compounds runt-of-the-litter calculations and assumptions to make a worst-case estimate of sulforaphane content in one tablespoon of broccoli seeds:

  • Broccoli seed weight of one tablespoon is 10.7 grams.
  • Worst-case sulforaphane weight in one tablespoon of broccoli seeds (10.7 g x 2.43 mg sulforaphane per gram of seeds) = 26.0 mg.

I won’t calculate sulforaphane weight after microwaving because part of the 3-day study processing for analysis was:

“Broccoli seeds were comminuted by analysis grinder. Seed powder (0.5g) was immersed in distilled water at 55 °C for 5 min to inactivate the epithiospecifier protein.”

Grinding seeds into powder then heating it probably incorporates any effects of microwaving intact broccoli seeds up to 60°C.


Our second discussion topic came by gathering study data from Broccoli or Sulforaphane: Is It the Source or Dose That Matters?

Assessing these 200 μmol amount / 35 mg weight sulforaphane supplement dose studies:

  1. Peak plasma statistics ranged from 0.5 μmol in Row 2 (n = 20) to 2.15 (n = 4) μmol in Row 1. Row 4 (n = 10) statistics don’t show it, but its individual peak plasma ranges per the below graphic were 0.359 μmol to 2.032 μmol. Coincidentally, the Row 4 subject (#2) who had the lowest peak plasma amount also had the lowest urinary % of dose excreted (also termed bioavailability) of 19.5%, and the Row 4 subject (#8) who had the highest peak plasma amount also had the highest sulforaphane bioavailability of 86.9%.
  2. From the Row 4 study: “The half-life of SF in the body was 2.07 ± 0.26 h as calculated from serum area-under-the-curve determinations.” Its Subject #2 had the longest sulforaphane half-life at 2.709 hours.
  3. The peak time after dose ranged from 1 to 3 hours. Not sure why Row 4 didn’t calculate a peak time, but eyeballing the above graphic showed that all subjects peaked between 1 and 2 hours. Row 2’s time was at the study’s first of three measurement intervals (3, 6, and 12 hours). Its peak time after dose probably also took place between 1 and 2 hours.

These four studies showed that there’s wide variation among individual responses to sulforaphane supplements. Row 4 study’s Concluding Remarks ended with:

“Innate metabolic differences must not be discounted when assessing the metabolism of SF alone, delivered in supplements.”


The first of A pair of broccoli sprout studies was Row 2 (n = 20) above. Its sulforaphane supplement statistics – repeated in the below graphic’s BSE (broccoli sprout extract) column – demonstrated how humans’ sulforaphane supplement metabolic profiles were different than our fresh broccoli sprout metabolic profiles:

The divided dose was twelve hours apart at breakfast and dinner times. Also, its first measurements weren’t taken until 3 hours after ingesting, which explains its later times with lesser amounts than the above sulforaphane supplement studies’ earlier times with greater amounts.

During Week 9 of Changing to a youthful phenotype with broccoli sprouts I changed my practices to eat microwaved broccoli sprouts at breakfast and dinner times from its finding:

“In sprout consumers, plasma concentrations were 2.4-fold higher after consuming the second dose than after the first dose.”

A metabolic profile resulting from my current practices is probably between the Sprout and BSE divided-dose statistics:

  • Sulforaphane intake is greater than eating raw broccoli sprouts because microwaving 3-day-old broccoli sprouts creates sulforaphane in them before eating.
  • Sulforaphane uptake from microwaved broccoli sprouts is quicker than eating raw broccoli sprouts. It may not be as immediate as taking sulforaphane supplements, which are usually powders.
  • Sulforaphane dose from microwaved broccoli sprouts is less dependent on an individual’s metabolism than eating raw broccoli sprouts.
  • Sulforaphane release from microwaved broccoli sprouts probably continues on to the gut as does eating raw broccoli sprouts. Sulforaphane release from supplements may not per Does sulforaphane reach the colon?.

The microwaving study processed 10 grams of broccoli florets immersed in 500 ml water with a 950W microwave on full power for 108 seconds to achieve 60°C. I microwave 65.5 grams of 3-day-old broccoli sprouts immersed in 100 ml water with a 1000W microwave on full power for 35 seconds to ≤ 60°C.

After microwaving I wait five minutes to allow further myrosinase hydrolization of glucoraphanin and other glucosinolates into sulforaphane and other healthy compounds. Enhancing sulforaphane content provided evidence that myrosinase hydrolization peaks at one minute after achieving 60°C per the below graphic:

I interpret the above sulforaphane degradation from minutes 1 to 5 to be leaching caused by leaving the broccoli sample immersed in water. I strain water from broccoli sprouts after microwaving – the Time 0 mark of the above graphic – because without leaching water, further hydrolization may increase sulforaphane.


Sulforaphane supplements:

  • Are readily metabolized,
  • Blood plasma levels peak by two hours, and
  • Blood plasma levels dissipate by eight hours.

To the extent a metabolism resulting from my current practices is closer to a sulforaphane supplement profile than a raw broccoli sprouts profile, maybe that leaves the door open to a microwaved broccoli seed dose at lunch time? In any event, there are seeds in each batch that don’t germinate after soaking for 12 hours and rinsing three times a day, and I eat them after microwaving anyway.

See Caution on broccoli seed erucic acid content? if you’re concerned about that.

Measuring sulforaphane plasma compounds

This 2020 Australian human study investigated methods of measuring sulforaphane plasma compounds:

“A simplified methodology to allow high-throughput LC–MS [Liquid Chromatography-Mass Spectrometry] analysis of plasma samples for measurement of sulforaphane and its metabolites is described. Analysis time is greatly reduced by employing fast chromatography and simple plasma extraction procedure.

Participants were observed consuming four Broccomax capsules, each containing 30 mg of broccoli seed extract and a dose of 8 mg of sulforaphane, as per manufacturer certificate of analysis, resulting in a total dose of 32 mg of sulforaphane (120 mg of broccoli seed extract).

Mean peak of combined metabolites from our study (0.9 and 1 μM) using 120 mg of broccoli seed extract (~32 mg of SFN) was similar to work by Fahey et al. who investigated pharmacokinetics of 350 mg of purified broccoli seed powder (mean 1.3 μM ± 0.5 μM), though our dose was almost three-times less. Pharmacokinetic profiles of our study mirrored those of Fahey et al. in that excretion was complete 8 hrs after consumption. Our intervention peaked slightly later (~2hrs), than that of Fahey (~1 hr), likely due to our use of a capsule rather than liquid.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7070302/ “Measuring Sulforaphane and Its Metabolites in Human Plasma: A High Throughput Method”


This study was thin on comparing their n = 2 results to previous work. Here are comparables from Broccoli or Sulforaphane: Is It the Source or Dose That Matters?


These researchers set up a strawman by stating a false comparison:

“Our dose was almost three-times less.”

The compared study was the n = 10 subjects row above, which stated its dose as:

“200 μmol of SF was contained in about 350 mg of SF-αCD powder dissolved in 25 mL of distilled water, which subjects were given to drink upon arrival at the clinic.”

If the current study wanted a true comparison, they would measure and compare sulforaphane dose weights or amounts:

  • https://pubchem.ncbi.nlm.nih.gov/compound/sulforaphane lists sulforaphane’s molecular weight as 177.3 g / mol.
  • A 5.64 μmol sulforaphane amount (.001 / 177.3) equals a 1 mg weight of sulforaphane.
  • 200 μmol / 5.64 μmol = 35 mg sulforaphane used in the compared study.

But these researchers couldn’t even do that! They asserted a 32 mg sulforaphane dose “per manufacturer certificate of analysis” when they had the resources to do otherwise!

What kind of study design would go to all the trouble of measuring plasma sulforaphane metabolite outputs, but not measure their sulforaphane input dose???

Had they closely read the compared study, they may have also noticed that its commercial supplement, Prostaphane, was tested to verify stated dosage. These researchers could have done the same with Broccomax.

Microwave broccoli to increase flavonoid levels

This 2019 USDA study investigated representative broccoli cooking methods for their impact on kaempferol and quercetin levels:

“Understanding cooking effects on flavonoids is crucial to accurately estimate their daily intake and further investigate their health benefits. The purpose of this study was not to compare different conditions of each cooking methods, but to focus on retentions of individual flavonoids under common cooking conditions in the US:

  • For boiling, we chose to use 85 seconds.
  • A 5-minute steaming time was used.
  • Microwave treatment was carried out in a 1200W microwave at full power for 1 minute.

Seven kaempferol (Km) glycosides and one quercetin (Qn) glycoside were identified and quantified in raw and cooked broccoli by HPLC-MS:

Boiling resulted in significant loss of all flavonoids, while steaming and microwaving led to minor losses or even increases of flavonoids.

Microwaving without water or with small amount of water tended to retain or increase total phenolics and/or flavonoids. When a large amount of water was added during microwaving, to some extent resembling boiling, total phenolics and/or flavonoids decreased.

Different agriculture practices may affect flavonoids’ existence and their interactions with other compounds, which in turn alter their sensitivity to heat treatments.

Retention of nutrients in cooked foods can be calculated as apparent retention (AR) based on dry form, or true retention (TR) based on fresh/wet form. TR represents actual consumption forms and also takes weight change after cooking into consideration.

The possible explanation for TR over 100% is that thermal processing may increase extractability and/or release from binding to other compounds as a result of matrix softening.”

https://www.cell.com/heliyon/fulltext/S2405-8440(19)30568-7 “Effects of domestic cooking on flavonoids in broccoli and calculation of retention factors”


The Material and methods section didn’t state that heated products’ temperatures were measured. So there wasn’t sufficient evidence for a solely thermal explanation of only microwaving achieving percentages over 100 per:

“The possible explanation for TR over 100% is that thermal processing..”

A more plausible explanation similar to Microwave broccoli to increase sulforaphane levels may account for microwaving’s increased percentages:

“Microwave treatment causes a sudden collapse of cell structure due to the increase in osmotic pressure difference over vacuole membrane.

We didn’t expect this result, and think microwave irradiation might help to release more conjugated forms of glucosinolates and then get hydrolyzed by released myrosinase.”


I immerse 3-day-old broccoli sprouts in 100 ml distilled water, then microwave them on 1000W full power for 35 seconds to ≤ 60°C (140°F). After microwaving I transfer broccoli sprouts to a strainer, and allow further myrosinase hydrolization of glucoraphanin and other glucosinolates into sulforaphane and other healthy compounds.

Myrosinase deactivation above 60°C wasn’t a consideration, since boiling, steaming, and a 1200W microwave on full power for one minute may have produced temperatures above 60°C. I’ll guess that an active enzyme wasn’t a requirement for flavonoid contents of broccoli purchased in a Beltsville, Maryland, grocery store.

The microwave tests used:

“Broccoli florets (150 g) were put in a microwave safe bowl with a 1 tablespoon [15 ml] of water.”

I use:

  • A lesser weight of 3-day-old broccoli sprouts;
  • A greater volume of distilled water;
  • A less powerful microwave operated on full power for a lesser duration.

Before microwaving, I would expect a estimated 134 mg total flavonoids from eating 3-day old broccoli sprouts every day. This study’s findings lead me to expect that current practices with microwaving would improve flavonoid levels.

Don’t overcook broccoli

This 2020 US / Korea study set a low bar and jumped over it by finding:

“The abundance of GSL [glucosinolate] hydrolysis products in cooked samples was lower compared to the raw samples.

Regardless of different cooking methods and durations, the total GSL amount in MeJA [methyl jasmonate]-treated broccoli was still higher than in the non-treated broccoli. This suggests that the increased GSL concentration in broccoli samples was solely affected by MeJA treatment, and the effect of MeJA was not affected by cooking methods.

Effect of cooking and 250 µM MeJA treatment on (A) total aliphatic glucosinolates, (B) total indole glucosinolates, and (C) total glucosinolates in ‘Green Magic’ broccoli. * = detected significant different by Student’s T-test (p ≤ 0.05, n = 3) with a significant interaction between MeJA treatment and cooking treatment.”

https://www.mdpi.com/2304-8158/9/6/758/htm “Methyl Jasmonate Treatment of Broccoli Enhanced Glucosinolate Concentration, Which Was Retained after Boiling, Steaming, or Microwaving”


Did it advance science to only replicate mistakes in consumer broccoli cooking methods with:

“The abundance of GSL hydrolysis products in cooked samples was lower compared to the raw samples.”

No.

Did the study design have tests to provide cooking method guidance for:

“To date, methods of delivering cooked broccoli without losing its nutritional benefits are still lacking in the literature, although consuming cooked broccoli is the most common practice for consumers.”

No.

Were there cooking method and temperature recommendations to avoid:

“Cooking also inactivates myrosinase, the enzyme converting GSL into hydrolysis products, and then hinders the formation of hydrolysis products.”

No.

Were there cooking method tests to further enhance either control samples or:

“Exogenous methyl jasmonate (MeJA) treatment was known to increase the levels of neoglucobrassicin and their bioactive hydrolysis products in broccoli.”

No.

Why omit temperature measurements since:

“The major research questions of this study were to evaluate how MeJA application to broccoli plants will affect GSL concentration, myrosinase activity, GSL hydrolysis product amounts..”

Maybe Microwave broccoli to increase sulforaphane levels wasn’t yet published when this study’s design decisions were made. Still, why would a study:

  • Test microwave half power without also testing full power?
  • Select microwaving time as the sole measurement without also measuring temperature?

Table S1 and Figure 3 of the Chinese / USDA study showed a two-minute microwaving time at 50% power wouldn’t be expected to have any sulforaphane content significantly different from uncooked broccoli. Also, temperatures of a five-minute microwaving time at 50% power were guaranteed to completely deactivate myrosinase.

Supplementary material confirmed that this study’s microwaving parameters didn’t show anything of value for how to use your microwave to increase broccoli compound levels. Did the study’s findings provide much more than what not to do?

Poor design decisions created a large gap between what could have been studied and what was studied. Let’s hope there will be better use of resources next time.

Part 2 of Do broccoli sprouts treat migraines?

To follow up Do broccoli sprouts treat migraines? which used a PubMed “sulforaphane migraine” search, a PubMed “diindolylmethane” search came across a 2020 Czech human cell study Antimigraine Drug Avitriptan Is a Ligand and Agonist of Human Aryl Hydrocarbon Receptor that Induces CYP1A1 in Hepatic and Intestinal Cells that had this informative Introduction:

“The aryl hydrocarbon receptor (AhR) transcriptionally controls a wide array of genes. AhR is a critical player in human physiology (e.g., hematopoiesis) and also in many pathophysiological processes such as diabetes, carcinogenesis, inflammation, infection or cardiovascular diseases.

Suitable candidates for off-targeting AhR could be the antimigraine drugs of triptan class, which have an indole core in their structure. Indole-based compounds were demonstrated as ligands of AhR, including dietary indoles (e.g., indole-3-carbinol and diindolylmethane).”

Adding AhR to the search showed:

Changing the PubMed search to “icz migraine” pulled up a 2013 review Biomedical Importance of Indoles that described sumatriptan as an indole, and:

“Since DIM accumulates in the cell nucleus, it likely contributes to cell nuclear events that have been ascribed to I3C.”

Widening the search to “i3c ahr” added:

Changing the search to “i3c migraine” picked up a 2011 UK human study Effect of diindolylmethane supplementation on low-grade cervical cytological abnormalities: double-blind, randomised, controlled trial:

“In the study reported here, there was no statistically significant difference in serious adverse events between groups; in fact a higher proportion of women in the placebo group reported a serious adverse event. Although this study did not have sufficient power to study migraines, we did find a non-significant increase in reported headaches (18% on DIM, 12% on placebo, P=0.12).”

Returning to the original PubMed “sulforaphane migraine” search, Bioavailability of Sulforaphane Following Ingestion of Glucoraphanin-Rich Broccoli Sprout and Seed Extracts with Active Myrosinase: A Pilot Study of the Effects of Proton Pump Inhibitor Administration included one subject who took migraine medication. They weren’t a study outlier, however.


Although indole chemistry indicates a broccoli sprouts – migraine connection, I haven’t found relevant research. Maybe the known properties and actions of broccoli sprout compounds provide enough to affect causes of migraines?

See Part 3 to follow up.