Articles

The Most Amazing Antioxidant and Detoxifier: Sulphoraphane in Broccoli Seed Extract

By Graeme Bradshaw

According to the National Academy of Science, broccoli and broccoli sprouts contain the largest amounts of glucosinolates and sulphoraphane—which are potent inducers of enzymes that protect against chemical carcinogens and involve in liver detoxification.

In its raw form, broccoli has a substance called myrosinase inside it, which converts to sulphoraphane when eaten. But if it's cooked for more than a four-minute steam, broccoli rapidly loses this compound, along with it many of the health benefits.

You can pair the broccoli with broccoli sprouts, mustard, horseradish, or wasabi—the spicier the better. Such combinations will provide more sulphoraphane than any one on their own. If you're not a fan of culinary spice, you can use radishes, cabbage, arugula, watercress, and Brussels sprouts.

Sulphoraphane from broccoli is efficiently and rapidly absorbed in our small intestine, then distributed throughout our body, providing really potent health benefits to many vulnerable tissues.

The Detox Mechanism—Phase I and Phase II

The mechanism in which our cells detoxify potentially harmful compounds—including many cancer-causing substances (carcinogens)—involves a so-called Phase I component in the liver that’s associated with the Cytochrome P450 system. It is then followed by a Phase II component where the intermediate compound produced by Phase I is bound in a way that permits ready excretion.

For a safe and efficient detoxification, toxins should ideally undergo a relatively slow Phase I reaction followed by a more rapid Phase II in order to prevent accumulation of the Phase I metabolite, which can be more toxic than its precursor.

Sulphoraphane from broccoli extracts stimulates this system perfectly and powerfully. Sulphoraphane can slightly slow down some parts of Phase I, and also acts as a inducer of Phase II.

The indole compounds (such as I-C-3 and DIM) from mature broccoli stimulate both Phase I and Phase II, which is less than ideal but still good for us.

Of clinical significance is the finding that Phase II enzymes have a relatively long half-life, so that up-regulated expression of these enzymes can remain for several days. Thus just three serves of broccoli or sulphoraphane per week can have very protective effects, as shown in hundreds of population studies.

Phase II enzymes are induced by a component called Nrf2, and sulphoraphane is a potent Nrf2 inducer. Consider Nrf2 as responsible for induction of a myriad of cellular defenses [2b]. The downstream enzyme products of Nrf2 target genes are efficient and versatile. They include the glutathione and thioredoxin systems, the major cellular reducing or anti-oxidant systems in our body.

Several reasons explain why Nrf2 induced enzymes are efficiency and versatility: firstly they are not consumed as they work as are direct-acting antioxidants such as vitamin C and E; secondly their duration of action is long with half-lives measured in days; and thirdly they restore the internally produced direct-acting antioxidants like coenzyme Q10 and the vitamin E by returning them to the active, or so-called reduced state.

Another interesting interaction is with Vitamin D. Vitamin D’s protective effects on human cells are well recognized, and like sulphoraphane it touches beneficially upon many hundreds of genes. It is nutritionally significant that the vitamin D receptor (VDR) is an Nrf2 target gene inducible by sulphoraphane; in turn, vitamin D can increase Nrf2 expression so these two compounds are synergistically beneficial to health.

So we have established some of the beneficial anti-aging effects via Nrf2 stimulation: animal and human studies show significant decline in Nrf2 activity between youth and old age.

Crucifer Sprouts May Protect Against Carcinogenic Development

A related enzyme stimulated by Nrf2 is NQO1. The activity of this is measurable and is used as a rapid screening procedure and a biomarker of the anti-carcinogenic activity of phytochemicals. [2c]

When several crucifers were compared for their Nrf2/NQO1 inducer effect, sulphoraphane returned ~33,000 units of NQO1 inducer activity per gram of fresh weight for broccoli, cabbage returned ~11,000 units, kale returned ~10,000 units, while turnip returning just ~2,000 units. [2c].

“Large quantities of inducers of enzymes that protect against carcinogens can be delivered in the diet by small quantities of young broccoli sprouts which contain as much inducer activity as 10–100 times larger quantities of mature vegetables” [2]. Small quantities of crucifer [broccoli] sprouts may protect against the risk of cancer as effectively as much larger quantities of mature vegetables of the same variety. [2]

In short, Broccoli is the best mature vegetable to eat, but the sprouts are even better!

As we will see from research below, our eyes, brain, lungs, breasts, colon and prostate as well as liver and kidneys gain benefits from the protection that sulphoraphane produce in our cells.

The chemoprevention properties of sulphoraphane against cancer are through both “blocking” and “suppressing” effects [3]. The “blocking” function of sulphoraphane is achieved through inhibiting Phase I metabolism enzymes that convert pro-carcinogens to carcinogens and inducing Phase II metabolism enzymes that promote excretion of carcinogens [3, 33].

Subsequent studies revealed the “suppressing” effects of sulphoraphane in modulating diverse cellular activities to inhibit the growth of transformed cells [3, 4, 5, 7, 8, 9, 32].

So sulphoraphanes block carcinogens [33] and suppress cells becoming cancerous, as we shall see in following research. [5b, 32].

The Health Benefits:

1. Reduced Breast Cancer Cells

The existence of cancer stem cells (CSCs) in breast cancer has profound implications for cancer prevention. In one study, the evaluated sulphoraphane, a natural compound derived from broccoli/broccoli sprouts, for its efficacy to inhibit breast cancer stem cells and its potential mechanism. Breast cancer is initiated from and maintained by a small population of breast cancer stem cells. Their studies were both in the test tube and in live mice. The test tube assay and another test called mammosphere formation assay showed that sulphoraphane inhibited breast cancer stem cells in vitro (i.e. “in glass” a lab situation), and eliminated breast cancer stem cells in vivo (means in the living animal). [5]

Study conclusions: “These studies support the use of sulphoraphane for breast cancer chemoprevention”. [5]

In a subsequent pilot study, eight healthy women undergoing reduction mammoplasty were given a single dose of a broccoli sprout preparation containing 200 mmol of sulphoraphane. Following oral dosing, sulphoraphane metabolites were readily measurable in human breast tissue enriched for epithelial cells. These findings provide a strong rationale for evaluating the protective effects of a broccoli sprout preparation in clinical trials of women at risk for breast cancer.” [5b]

There are many other positive breast-cancer related studies so these are a sample only.

2. Reduced Prostate Cancer Cells in Animal Studies

Prostate and colon cancer have both also been shown to be responsive to sulphoraphanes. Diets high in cruciferous vegetables are associated with lower risk of incidence of prostate cancer, including aggressive forms of this disease. One study showed that men with the glutathione S transferase M1 (GSTM1)-present genotype and high broccoli intake had the greatest reduction in risk— basically reducing risk of prostate cancer by half in this vulnerable group. [7]

The findings provide evidence that two or more servings per month of cruciferous vegetables may reduce risk of prostate cancer, especially among men with GSTM1-present alleles, and are consistent with a role of dietary sulphoraphane as chemopreventive agents against prostate cancer.[7]

Human intervention studies with sulphoraphane show that it induced cell death in human prostate cancer cells. This was initiated by reactive oxygen species—meaning sulphoraphane kills cancer cells in rats by oxidizing them to death.[8] It was also found that taking N-acetyl cysteine at the same time counteracted this beneficial effect. [8]

3. Protects Our Lungs From Pollution

Broccoli extract also protects the lungs, potentially from cancer, certainly from pollutants.

As we now know naturally occurring sulphoraphane from broccoli sprouts induce a potent increase in antioxidant Phase II enzymes such as glutathione, but that occurs not only in the liver but also in lung airway cells. A study conclusion stated: “Oral sulphoraphane safely and effectively induces mucosal Phase II enzyme expression in the upper airway of human subjects. This study demonstrates the potential of antioxidant Phase II enzymes induction in the human airway as a strategy to reduce the inflammatory effects of oxidative stress, a novel therapeutic strategy for oxidant induced airway disease.“ Similar effects are gained with wasabe, or horseradish, both cabbage family plants with potent sulphoraphane nasal clearing and detoxing benefits. [9]

Translated, this means sulphoraphane protects the lungs from pollution and smoke.

4. Protects Our Eyes From Aging

A study suggests that sulphoraphane enhances the ability of human retinal pigment epithelial cell against oxidative stress. The results show that sulphoraphane may be a valuable supplement for preventing and retarding the development of Age Related Macular Degeneration. [10]

5. Protects Our Kidneys and Bladder

These protective effects are mediated by activating Nrf2, a protein that regulates the expression of antioxidant proteins that protect against oxidative damage triggered by injury and inflammation, prevent oxidative and inflammatory stressors to the kidneys and bladder, two organs sensitive to pollution induced damage and cancers. Diabetic Neuropathies and kidney damage from poisons may also be managed with sulphoraphanes. [11-18]

So it turns out that Broccoli sprouts are the richest food source of sulphoraphane, and these are proven to be cancer protective, and as we will see protect our eyes, kidneys, bladder brain, heart and nerves from oxidative damage.

Furthermore sulphoraphanes protects the brain.

6. Protects Our Brain

Broccoli sprouts have helped many autistic young men, through improvements in detoxification, which is well documented as dysfunctional in autistics. Broccoli sprouts seem to help according to one study.

In a placebo-controlled, randomized, double-blind clinical trial, daily oral administration of broccoli sprout extract for 18 weeks to 29 young men with autistim substantially improved behavior compared with 15 placebo recipients.

Behavior was quantified by both parents/caregivers and physicians by three widely accepted measures. Regarding social behaviour 46% (12 of 26), 54% (14 of 26), and 42% (11 of 26) of sulphoraphane recipients were much or very-much improved on social interaction, aberrant behavior, and verbal communication, respectively, compared with 0%, 9%, and 0% respectively, for placebo recipients. There were similar percentages of changes in aberrant behaviours in the young autistic men.[19] Extensive evidence shows that sulphoraphane counteracts many of the same biochemical and molecular abnormalities associated with ASD, including oxidative stress and reduced antioxidant capacity, defects in glutathione synthesis, and neuro-inflammation. [20]

We can expect that broccoli sprout extract is able to protect nerves and improve the brains function for us all from these and other studies. For a technical look into the brain protective effects see the following article [21] which in summary says: “ the observed protective effects of sulphoraphane against brain oxidative stress are mainly associated with Nrf2 activation and the resulting upregulation of antioxidant cytoprotective proteins and elevation of glutathione.

The sulphorapanes benefits have been shown to repair a damaged blood brain barrier (so called “leaky brain”). [22-23]

7. Heals Traumatic Brain Injury (TBI)

Traumatic Brain Injury - concussion - increases long-term mortality and reduces life expectancy. It is associated with increased incidences of seizures, sleep disorders, neurodegenerative diseases, neuroendocrine dysregulation, and psychiatric diseases, as well as non-neurological disorders such as sexual dysfunction, bladder and bowel incontinence, Alzheimer’s disease and systemic metabolic dysregulation that may arise and/or persist for months to years post-injury.

Sulphoraphane enhances decreases cerebral edema (swelling) following traumatic brain injury. [27] Administration of sulphoraphane to traumatic brain injured mice resulted in an up-regulation of Nrf2-dependent antioxidant enzymes and a reduction of oxidative damage after Traumatic Brain Injury (TBI). In accordance with these biochemical changes, sulphoraphane also significantly reduced neuronal death, contusion volume, and neurological dysfunction after TBI. [28]

Sulphoraphanes protect against the damaging effects of amyloid beta, the key compound related to Alzheimers disease. There is some hope from animal studies of a protective benefit in Alzheimers in that they showed amelioration of cognitive function in behavior tests. Animal studies also showed the antioxidant glutathione had beneficial effects in Parkinsons Disease models. [29-32]

8. Benefits the Cardiovascular System

Suffice it to say that of all vegetables studied it is the cabbage/broccoli family with the most protective effects, according to a 2015 study “Phyto-chemical compounds and protection from cardiovascular diseases: a state of the art”. [32b]

Is Sulphoraphane More Powerful than Antioxidant Vitamins?

Yes, by far.

What has become clear is that attempts to counter oxidative stress by “antioxidant” vitamin supplementation don’t prove well in studies. [34] In a meta-analysis by the Cochraine group they found that synthetic antioxitants found in many supplements fail to produce disease preventing results when studied: “The slightly increased risk of mortality [3%] was associated with beta-carotene and possibly [synthetic] vitamin E and [synthetic] vitamin A. The current evidence does not support the use of [synthetic man made] antioxidant supplements in the general population or in patients with various diseases”. [34]

That is a strong science based statement by this respected Cochraine group. See the reference if you would like to see how extensive the research is behind the statement.

Yet we know that plant based antioxidants do protect from illness, and sulphoraphanes and the turmeric extract curcumin are the most powerful, as found in many studies some here reported.

Natural carotenoids and natural vitamin E and C when found in food come in synergistic forms of several compounds - and are much more complex than synthetic vitamin A, synthetic beta carotene, and man made tocopherols (most vitamin E) found in a standard vitamin supplement.

I think the routine vitamin supplement if it is an antioxidant formula, and not derived from foods is a waste of money.

On the other hand, sulphoraphane from broccoli and curcumin from tumeric are among the best documented protective health inducers with proven anticancer and other health benefitting properties, and whose molecular mechanisms have been extensively investigated [32-38].

The main purpose of one mice study was to compare vitamin supplements with food based antioxidants, showed the only sulphoraphane and phytonutrient based approach worked. [39]

For a full review article see sulphoraphane and Other Nutrigenomic Nrf2 Activators: Can the Clinician’s Expectation Be Matched by the Reality? [32]

The comments by these experts state: “Broccoli-derived sulphoraphane emerges as a phytochemical with the capability of … favourably modifying genes associated with chemoprevention”. Compared with widely used phytochemical-based supplements like curcumin, silymarin, and resveratrol, sulphoraphane more potently activates Nrf2 to induce the expression of a battery of cytoprotective genes. Both its high bioavailability and significant Nrf2 inducer capacity contribute to the therapeutic potential of sulphoraphane-yielding supplements.” [32]

Conclusion

Compared with widely used vitamins or other phytonutrient or herbal supplements like curcumin, silymarin (milk thistle), and resveratrol (red wine extract), sulphoraphane more potently activates Nrf2 to induce the expression of a battery of protective genes and improves glutathione levels as part of this effect. Glutathione is the master anti-oxidant gobbling up and eliminating many pollutants, including air pollutants and heavy metals.

Broccoli seed extracts are the most potent source of sulphoraphanes, and are easily obtained in capsules. Two daily, or even most days a week are highly effective at raising our cellular defenses, so vital in polluted environments.

Curcumin, the turmeric extract, is also excellent as a phytonutrient. Curcumin assists sulphoraphane, and it has more anti-inflammatory benefits, also thinning the blood in a safer way than does aspirin.

Vitamin D3 is also synergistic with sulphoraphane, with its own immune protective and anti-cancer benefits being well established by hundreds of studies.

I believe there is no other supplement can protect our health better than sulphoraphane from broccoli seed extract.

 

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