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Sulforaphane, C6H11NOS2,
CAS 4478-93-7
Sulforaphane is known as an anticancer, antidiabetic, and
antimicrobial chemical compound. It can be obtained by eating cruciferous
vegetables (broccoli, brussel sprouts, bok choy, cabbage, cauliflower, kale,
collards, broccoli sprouts, kohlrabi, mustard, turnip, radish, arugula,
watercress, etc.).
The enzyme myrosinase transforms glucoraphanin (a glucosinolate) into
sulforaphane upon damage to the plant (such as from chewing)
Image by Interchemistry.com
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"Broccoli has recently entered the public awareness as a preventive dietary agent. This study supports the emerging evidence that broccoli sprouts may be able to prevent cancer in humans, not just in lab animals," said Jed Fahey, Sc.D., a faculty research associate in the Department of Pharmacology at Johns Hopkins School of Medicine. Researchers assessed the severity of H. pylori infection at enrollment, and again at four and eight weeks using standard breath, serum and stool tests. H. pylori levels were significantly lower at eight weeks on all three measures among those patients who had eaten broccoli sprouts, while they remained the same for patients who had eaten alfalfa sprouts. A reduction in H. pylori is expected to lead to a reduction in stomach cancer due to their well-established cause-and-effect link. Stomach cancer has a grim prognosis and is the second most common and the second deadliest cancer worldwide.
Press release of the Johns Hopkins
Medical Institution: Gutsy germs
succumb to baby broccoliA small, pilot study
in 50 people in Japan suggests that eating two and a half ounces of
broccoli sprouts daily for two months may confer some protection
against a rampant stomach bug that causes gastritis, ulcers and even
stomach cancer. Citing their new "demonstration
of principle" study, a Johns Hopkins researcher and an international
team of scientists caution that eating sprouts containing sulforaphane
did not cure infection by the bacterium Helicobacter pylori (H.
pylori). They do not suggest that eating this or any amount of
broccoli sprouts will protect anyone from stomach cancer or cure GI
diseases. However, the study does show that
eating a daily dose of broccoli sprouts reduced by more than 40
percent the level of HpSA, a highly specific measure of the presence
of components of H. pylori shed into the stool of infected people.
There was no HpSA level change in control subjects who ate alfalfa
sprouts. The HpSA levels returned to pretreatment levels eight weeks
after people stopped eating the broccoli sprouts, suggesting that
although they reduce H. pylori colonization, they do not eradicate it.
"The highlight of the study is that we identified a food that, if
eaten regularly, might potentially have an effect on the cause of a
lot of gastric problems and perhaps even ultimately help prevent
stomach cancer," says Jed W. Fahey, M.S., Sc.D., an author of the
paper who is a nutritional biochemist in the Lewis B. and Dorothy
Cullman Cancer Chemoprotection Center at the Johns Hopkins University
School of Medicine. The discovery that
sulforaphane is a potent antibiotic against H. pylori was reported in
2002 by Fahey and colleagues at Johns Hopkins. "Broccoli sprouts have
a much higher concentration of sulforaphane than mature heads," Fahey
explains, adding that further investigation is needed to affirm the
results of this clinical trial and move the research forward. The
study, published April 6 in Cancer Prevention Research, builds on
earlier test-tube and mouse studies at Johns Hopkins and elsewhere
about the potential value of sulforaphane, a naturally occurring
biochemical found in relative abundance in fresh broccoli sprouts.
Sulforaphane appears to trigger cells in the body, including in the
gastrointestinal tract, to produce enzymes that protect against oxygen
radicals, DNA-damaging chemicals, and inflammation.
In the new report, the team also shows that when H. pylori-infected
mice sipped broccoli-sprout smoothies for eight weeks, there was up to
a fourfold increase in the activity of two of these key enzymes that
protect cells against oxidative damage. In addition, the number of
Helicobacter bacteria in the mice's stomachs decreased by almost a
hundredfold it did not change in infected control animals that drank
plain water. The researchers also noted a greater than 50 percent
reduction in inflammation of the primary target of this bacterium –
the body of the stomach – in treated mice but not in controls.
In a related experiment, the team fed the same dose of broccoli
sprouts for the same amount of time to H. pylori-infected mice that
had been genetically engineered to lack the Nrf2 gene that activates
protective enzymes. "These knock-out mice didn't respond," Fahey says,
which confirms previous findings for a role of Nrf2 in protection
against H. pylori-induced inflammation and gastritis.
Classified a carcinogen by the World Health Organization, H. pylori is
a gastrointestinal tract germ that manages to thrive in the lining of
the stomach despite the strength of natural acids there that rival
that of car batteries. Afflicting several billion people – roughly
half of the world's population – this corkscrew-shaped bacterium has
long been associated with stomach ulcers, which now are frequently
cured by antibiotics. Research strongly suggests that the bacteria
also are linked to high rates of stomach cancer in some countries,
that strains resistant to standard antibiotics are prevalent, and that
multiple courses of standard antibiotics do not always eliminate the
infection. Working in Japan where there is high
incidence of chronic H. pylori-infection, the research team gave 25 H.
pylori-infected subjects two and a half ounces (70 grams) per day of
broccoli sprouts for two months. Another 25 infected people consumed
an equivalent amount of alfalfa sprouts which, although rich in
phytochemicals, don't contain sulforaphane. The
researchers assessed the severity of Helicobacter infection at the
start of the study, after four and eight weeks of treatment, and again
eight weeks after intervention was stopped. They used breath tests to
assess colonization by H. pylori bacteria and blood tests to judge the
severity of inflammation in the stomach lining; in addition, they
looked for antigens in stool samples to help determine the extent of
the infections. "We know that a dose of a couple
ounces a day of broccoli sprouts is enough to elevate the body's
protective enzymes," Fahey says. "That is the mechanism by which we
think a lot of the chemoprotective effects are occurring.
"What we don't know is whether it's going to prevent people from
getting stomach cancer. But the fact that the levels of infection and
inflammation were reduced suggests the likelihood of getting gastritis
and ulcers and cancer is probably reduced." In
disclosure of a potential conflict of interest, Fahey is a cofounder
of, but holds no equity in, a company that is licensed by The Johns
Hopkins University to produce broccoli sprouts. A portion of the
proceeds is used to help support cancer research, but no such funds
were provided to support this study. "It's
exciting that a chronic bacterial infection that poses great hazards
to hundreds of millions of people globally can be ameliorated by a
specific dietary strategy," says Paul Talalay, M.D., John Jacob Abel
Distinguished Service Professor of Pharmacology and Experimental
Therapeutics and director of the Lewis B. and Dorothy Cullman Cancer
Chemoprotection Center at Johns Hopkins' Institute for Basic
Biomedical Sciences. Talalay directs the lab
where, in 1992, his team discovered the health-promoting properties of
sulforaphane. A longtime proponent of cancer prevention and
chemoprotection, Talalay eats fresh broccoli sprouts regularly, as
does Fahey. "I like them," Fahey says. "I eat
them all the time, but not every day. Variety is the spice of life: I
eat blueberries on the other days."
Abstract of Article [1]: The isothiocyanate sulforaphane [SF; 1-isothiocyanato-4(R)-methylsulfinylbutane] is abundant in broccoli sprouts in the form of its glucosinolate precursor (glucoraphanin). SF is powerfully bactericidal against Helicobacter pylori infections, which are strongly associated with the worldwide pandemic of gastric cancer. Oral treatment with SF-rich broccoli sprouts of C57BL/6 female mice infected with H. pylori Sydney strain 1 and maintained on a high-salt (7.5% NaCl) diet reduced gastric bacterial colonization, attenuated mucosal expression of tumor necrosis factor- and interleukin-1ß, mitigated corpus inflammation, and prevented expression of high salt-induced gastric corpus atrophy. This therapeutic effect was not observed in mice in which the nrf2 gene was deleted, strongly implicating the important role of Nrf2-dependent antioxidant and anti-inflammatory proteins in SF-dependent protection. Forty-eight H. pylori–infected patients were randomly assigned to feeding of broccoli sprouts (70 g/d; containing 420 µmol of SF precursor) for 8 weeks or to consumption of an equal weight of alfalfa sprouts (not containing SF) as placebo. Intervention with broccoli sprouts, but not with placebo, decreased the levels of urease measured by the urea breath test and H. pylori stool antigen (both biomarkers of H. pylori colonization) and serum pepsinogens I and II (biomarkers of gastric inflammation). Values recovered to their original levels 2 months after treatment was discontinued. Daily intake of sulforaphane-rich broccoli sprouts for 2 months reduces H. pylori colonization in mice and improves the sequelae of infection in infected mice and in humans. This treatment seems to enhance chemoprotection of the gastric mucosa against H. pylori–induced oxidative stress.
American Association for Cancer Research The mission of the American Association for Cancer Research is to prevent and cure cancer. Founded in 1907, AACR is the world's oldest and largest professional organization dedicated to advancing cancer research. The membership includes more than 28,000 basic, translational and clinical researchers; health care professionals; and cancer survivors and advocates in the United States and 80 other countries. The AACR marshals the full spectrum of expertise from the cancer community to accelerate progress in the prevention, diagnosis and treatment of cancer through high-quality scientific and educational programs. It funds innovative, meritorious research grants. The AACR Annual Meeting attracts more than 17,000 participants who share the latest discoveries and developments in the field. Special conferences throughout the year present novel data across a wide variety of topics in cancer research, treatment and patient care. The AACR publishes five major peer-reviewed journals: Cancer Research; Clinical Cancer Research; Molecular Cancer Therapeutics; Molecular Cancer Research; and Cancer Epidemiology, Biomarkers & Prevention. The AACR's most recent publication and its sixth major journal, Cancer Prevention Research, is dedicated exclusively to cancer prevention, from preclinical research to clinical trials. The AACR also publishes CR, a magazine for cancer survivors and their families, patient advocates, physicians and scientists. CR provides a forum for sharing essential, evidence-based information and perspectives on progress in cancer research, survivorship and advocacy.
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