Peach extract slows breast cancer growth and spread
Washington State University food
scientist and colleagues at Texas A&M have found that compounds in peaches
can inhibit the growth of breast cancer cells and their ability to spread.
Writing in the Journal of Nutritional Biochemistry, the researchers say the
compounds could be a novel addition to therapies that reduce the risk of
metastasis, the primary killer in breast and many other cancers. The compounds
could be given as an extract or, judging from the doses given mice in the
study, two to three peaches a day.
"I would do three peaches a
day," said Giuliana Noratto, WSU assistant professor of food science.
Study expands to other foods
The study also underscores the value
of good nutrition in preventing cancer, she said.
"Having enough fruits and
vegetables that can provide these compounds in our diet, we might have a
similar preventive effect," said Noratto. She is now looking at compounds
in wheat, barley, quinoa, apples and dairy products that could have a role in
preventing obesity-related diseases.
The research was part of her
doctoral work at Texas A&M with plant breeder David Byrne, food scientist
Luis Cisneros-Zevallos and toxicologist Weston Porter.
Medicinal plant tradition
She was drawn to the research after
doing work on the antioxidant activity of root plants in her native Peru.
"We have a huge tradition of
medicinal plants," she said. "We are great believers that you can
cure yourself by having a good diet and a good supply of medicinal
plants."
In 2009, Noratto and her colleagues
at Texas A&M published a study showing that peach and plum extracts
suppressed breast cancer cells cultured in petri dishes. For the new study, the
researchers implanted breast cancers cells beneath the skin of mice. The
technique, called a xenograft, is often used to look at the growth of breast
cancer cells in a living animal, mimicking the interactions by which tumors
form and progress.
Metastasis inhibited too
After giving the cells a week to
establish, the researchers fed the mice varying doses of peach polyphenols,
compounds that help plants ward off the damaging effects of the sun's
ultraviolet radiation.
"There are several studies
showing that these compounds act as antioxidants and can therefore protect DNA
against damage that can produce cancer," said Noratto, the first author of
both studies. Other researchers have seen that phenomenon, Noratto said, but
she and her colleagues wanted to know if the compounds might start a cascade of
signals that could induce the cancer cells to commit suicide.
"We didn't even think about
metastasis at that time," she said. "The surprise was we analyzed
lungs and beside the fact that the peach compounds inhibited the growth of the
tumor, they also inhibited the metastasis levels on the lungs."
Moreover, after 12 days the
researchers saw that mice fed with high levels of polyphenols had tumors that
grew less and without much of the blood vessel formation that can help cancer
cells spread to other parts of the body. The tumors in those mice also had less
evidence of enzymes involved in the spread and invasion of cancer.
The doses given the mice, if scaled
up to a 132-pound person, could be supplied by two to three peaches a day or a
dietary supplement of peach polyphenol extract powder.
Peaches, plums, nectarines fight obesity, diabetes, heart disease
Peaches, plums and nectarines have
bioactive compounds that can potentially fight-off obesity-related diabetes and
cardiovascular disease, according to new (June, 2012) studies by Texas AgriLife
Research.
The study, presented at the American
Chemical Society in Philadelphia showed that the compounds in stone fruits
could be a weapon against "metabolic syndrome," in which obesity and
inflammation lead to serious health issues, according to Dr. Luis Cisneros-Zevallos,
AgriLife Research food scientist.
"In recent years obesity has
become a major concern in society due to the health problems associated to
it," said Cisneros-Zevallos, who also is an associate professor at Texas
A&M University. "In the U.S., statistics show that around 30 percent
of the population is overweight or obese, and these cases are increasing every
year in alarming numbers."
While he acknowledged that
lifestyle, genetic predisposition and diet play a major role in one's tendency
toward obesity, "the major concern about obesity is the associated disease
known as metabolic syndrome.
"Our studies have shown that
stone fruits – peaches, plums and nectarines – have bioactive compounds that
can potentially fight the syndrome," Cisneros-Zevallos said. "Our
work indicates that phenolic compounds present in these fruits have
anti-obesity, anti-inflammatory and anti-diabetic properties in different cell
lines and may also reduce the oxidation of bad cholesterol LDL which is
associated to cardiovascular disease."
What is unique to these fruits, he
said, is that their mixture of the bioactive compounds work simultaneously
within the different components of the disease.
"Our work shows that the four
major phenolic groups – anthocyanins, clorogenic acids, quercetin derivatives
and catechins – work on different cells – fat cells, macrophages and vascular
endothelial cells," he explained. "They modulate different
expressions of genes and proteins depending on the type of compound.
"However, at the same time, all
of them are working simultaneously in different fronts against the components
of the disease, including obesity, inflammation, diabetes and cardiovascular
disease," he explained.
Cisneros-Zevallos said this is
believed to be the first time that "bioactive compounds of a fruit have
been shown to potentially work in different fronts against a disease."
"Each of these stone fruits
contain similar phenolic groups but in differing proportions so all of them are
a good source of health promoting compounds and may complement each
other," he said, adding that his team plans to continue studying the role
of each type of compound on the molecular mechanisms and confirm the work with
mice studies.
Peaches, plums induce deliciously promising death of breast
cancer cells
Breast cancer cells - even the most
aggressive type - died after treatments with peach and plum extracts in lab
tests at Texas AgriLife Research recently, and scientists say the results are
deliciously promising. Not only did the cancerous cells keel over, but the
normal cells were not harmed in the process.
AgriLife Research scientists say two
phenolic compounds are responsible for the cancer cell deaths in the study,
which was published in the Journal of
Agriculture and Food Chemistry. The phenols are organic compounds that
occur in fruits. They are slightly acidic and may be associated with traits
such as aroma, taste or color.
"It was a differential effect
which is what you're looking for because in current cancer treatment with chemotherapy,
the substance kills all cells, so it is really tough on the body," said
Dr. David Byrne, AgriLife Research plant breeder who studies stone fruit.
"Here, there is a five-fold difference in the toxic intensity. You can put
it at a level where it will kill the cancer cells - the very aggressive ones -
and not the normal ones."
Byrne and Dr. Luis Cisneros-Zevallos
originally studied the antioxidants and phytonutrients in plums and found them
to match or exceed the blueberry which had been considered superior to other
fruits in those categories.
"The following step was to
choose some of these high antioxidant commercial varieties and study their
anticancer properties," Cisneros-Zevallos said. "And we chose breast
cancer as the target because it's one of the cancers with highest incidence
among women. So it is of big concern."
According to the National Cancer
Institute, there were 192,370 new cases of breast cancer in females and 1,910
cases in males in 2009. That year, 40,170 women and 440 men died from breast
cancer. The World Health Organization reports that breast cancer accounts for
16 percent of the cancer deaths of women globally.
Cisneros-Zevallos, an AgriLife
Research food scientist, said the team compared normal cells to two types of
breast cancer, including the most aggressive type. The cells were treated with
an extract from two commercial varieties, the "Rich Lady" peach and
the "Black Splendor" plum.
"These extracts killed the
cancer cells but not the normal cells," Cisneros-Zevallos said.
A closer look at the extracts
determined that two specific phenolic acid components - chlorogenic and
neochlorogenic - were responsible for killing the cancer cells while not
affecting the normal cells, Cisneros-Zevallos said.
The two compounds are very common in
fruits, the researchers said, but the stone fruits such as plums and peaches
have especially high levels.
"So this is very, very
attractive from the point of view of being an alternative to typical
chemotherapy which kills normal cells along with cancerous ones," Byrne
added.
The team said laboratory tests also
confirmed that the compounds prevented cancer from growing in animals given the
compounds.
Byrne plans to examine more fully
the lines of the varieties that were tested to see how these compounds might be
incorporated into his research of breeding plums and peaches. Cisneros-Zevallos
will continue testing these extracts and compounds in different types of cancer
and conduct further studies of the molecular mechanisms involved.
Eating prunes helps prevent fractures and osteoporosis
When
it comes to improving bone health in postmenopausal women — and people of all
ages, actually — a Florida State University researcher has found a simple,
proactive solution to help prevent fractures and osteoporosis: eating dried
plums.
"Over
my career, I have tested numerous fruits, including figs, dates, strawberries
and raisins, and none of them come anywhere close to having the effect on bone
density that dried plums, or prunes, have," said Bahram H. Arjmandi,
Florida State's Margaret A. Sitton Professor and chairman of the Department of
Nutrition, Food and Exercise Sciences in the College of Human Sciences.
"All fruits and vegetables have a positive effect on nutrition, but in
terms of bone health, this particular food is exceptional."
Arjmandi
and a group of researchers from Florida State and Oklahoma State University
tested two groups of postmenopausal women. Over a 12-month period, the first
group, consisting of 55 women, was instructed to consume 100 grams of dried
plums (about 10 prunes) each day, while the second — a comparative control
group of 45 women — was told to consume 100 grams of dried apples. All of the
study's participants also received daily doses of calcium (500 milligrams) and
vitamin D (400 international units).
The
group that consumed dried plums had significantly higher bone mineral density
in the ulna (one of two long bones in the forearm) and spine, in comparison
with the group that ate dried apples. This, according to Arjmandi, was due in
part to the ability of dried plums to suppress the rate of bone resorption, or
the breakdown of bone, which tends to exceed the rate of new bone growth as
people age.
The
group's research, "Comparative Effects of Dried Plum and Dried Apple on
Bone in Post Menopausal Women was published August, 2011 in the British Journal of Nutrition. Arjmandi
conducted the research with his graduate students Shirin Hooshmand, Sheau C.
Chai and Raz L. Saadat of the College of Human Sciences; Dr. Kenneth Brummel-Smith,
Florida State's Charlotte Edwards Maguire Professor and chairman of the
Department of Geriatrics in the College of Medicine; and Oklahoma State
University statistics Professor Mark E. Payton.
In
the United States, about 8 million women have osteoporosis because of the
sudden cessation of ovarian hormone production at the onset of menopause.
What's more, about 2 million men also have osteoporosis.
"In
the first five to seven postmenopausal years, women are at risk of losing bone
at a rate of 3 to 5 percent per year," Arjmandi said. "However,
osteoporosis is not exclusive to women and, indeed, around the age of 65, men
start losing bone with the same rapidity as women."
Arjmandi
encourages people who are interested in maintaining or improving their bone
health to take note of the extraordinarily positive effect that dried plums
have on bone density.
"Don't
wait until you get a fracture or you are diagnosed with osteoporosis and have
to have prescribed medicine," Arjmandi said. "Do something meaningful
and practical beforehand. People could start eating two to three dried plums
per day and increase gradually to perhaps six to 10 per day. Prunes can be
eaten in all forms and can be included in a variety of recipes."
The
Bone-Boosting Benefits of Dried Plums
Fifty-seven
million Americans suffer from low bone density or osteoporosis, a disease which
causes bones to become so weak and brittle that even a minor fall or other
stresses may cause fractures.(1) A study published in the British Journal of Nutrition in July 2014 examined the mechanism of
the bone-protective properties of an unlikely source—California dried plums.(2)
To
further understand the mechanism by which dried plums (prunes) improve bone
health, researchers from San Diego State University and Florida State
University used data collected from a previous 12-month clinical trial that
compared the bone-protective effects of dried plums and dried apples.(3)
Results from this clinical trial confirmed the bone-protective properties of
dried plums, and several animal studies have also supported this finding.
However, the mechanisms by which dried plums impart their bone-protective
properties remain unclear.
“While
it is difficult to identify the exact mechanism behind dried plums’ positive
effect on bones, this study identified three potential pathways for the
mechanism behind the effect of dried plums on bone resorption and bone
formation,” explains Dr. Shirin Hooshmand, PhD, Assistant Professor Department
of Exercise and Nutritional Sciences at San Diego State University. “We are
excited to continue to apply the results of this study to future research that
may help us to determine the exact link between dried plums and healthy bones.”
During
the original 12-month clinical trial, which was published in 2011 in the
British Journal of Nutrition, 160 osteopenic, postmenopausal women were
randomly assigned to eat either 100 grams dried plums (about 10 dried plums)
daily or 75 grams dried apple daily. Each participant also received 500
milligrams of calcium plus a daily vitamin D supplement (400 international
units). The results indicated that the group that consumed dried plums had
significantly higher bone mineral density in the ulna (one of two long bones in
the forearm) and spine, in comparison with the group that ate dried apples.
This,
according to study author and researcher Dr. Bahram H. Arjmandi, PhD, RD,
Florida State University’s Margaret A. Sitton Professor of the Department of
Nutrition, Food and Exercise Sciences and Director of the Center for Advancing
Exercise and Nutrition Research on Aging (CAENRA) in the College of Human
Sciences, was due, in part, to the ability of dried plums to suppress the rate
of bone resorption, or the breakdown of bone, which tends to exceed the rate of
new bone growth as people age.
“Nature
has created dried plums to be unique in nutrient composition. They really are
the whole package,” explains Dr. Arjmandi. “In more than 15 years of research,
I have never seen a fruit like dried plums. Research suggests that dried plums
may actually help to regenerate bone in people who have experienced bone loss.
This is a serious issue for men and women alike, and dried plums continue to
show promising results in the prevention and reversal of bone loss.”
Results
of additional animal studies which measured effects on bone mineral density are
consistent, showing strong supporting evidence of an effect of dried plums on
bone mineral density and/or markers of bone turnover. Collectively, both the
human and animal studies indicate that adding dried plums to the diet may be an
effective way to help support healthy bones.
Research
also suggests dried plums may support heart health and digestive health and may
improve satiety:
•Dried
plums help manage weight through improved satiety, perhaps by producing lower
glucose and/or appetite-regulating hormone concentrations. (4)
•Dried
plums reduce LDL cholesterol in both animals and humans. (5)
•Dried
plums promote digestive health and are palatable and more effective than psyllium
for the treatment of mild to moderate constipation, and should be considered as
first-line therapy. (6)
•Dried
plums are considered a low-glycemic index (GI) food, which means they are
likely more satiating than high-GI foods and do not cause a large rise and fall
in blood glucose levels and insulin response after a meal.(7)
1.
Learn About Osteoporosis.” National Osteoporosis Foundation. Web. 15 October
2013. http://nof.org/learn.
2.
British Journal of Nutrition / Volume 112 / Issue 01 / July 2014, pp 55 - 60
3.
British Journal of Nutrition (2011), 106, 923–930.
4.
Furchner-Evanson A, Petrisko Y, Howarth L, Nemoseck T, Kern M. Type of snack
influences satiety responses in adult women. Appetite. 2010;54:564–569.
5.
Gallaher CM, Gallaher DD. Dried plums (prunes) reduce atherosclerosis lesion
area in apolipoprotein E-deficient mice. British Journal of Nutrition.
2009;101(2):233–239.
6.
Attaluri A, Donahoe R, Valestin J, Brown K, Rao SS. Randomised clinical trial:
dried plums (prunes) vs. psyllium for constipation. Alimentary Pharmacology and
Therapeutics. 2011;33:822–828.
7.
Foster-Powell, K., Holt, S.H.A., Brand-Miller, J.C. International table of
glycemic index and glycemic load values. The American Journal of Clinical
Nutrition. 2002.76:5-56.
Eating prunes can help weight loss
Research
by the University of Liverpool has found that eating prunes as part of a weight
control diet can improve weight loss.
Consumption
of dried fruit is not readily recommended during weight loss despite evidence
it enhances feelings of fullness.
However,
a study by the University's Institute of Psychology, Health and Society of 100
overweight and obese low fibre consumers tested whether eating prunes as part
of a weight loss diet helped or hindered weight control over a 12-week period.
It
also examined if low fibre consumers could tolerate eating substantial numbers
of prunes in their diet, and if eating prunes had a beneficial effect on
appetite.
To
assess the effects of prunes on weight and appetite, participants in the study
were divided into two groups – those who ate prunes every day (140g a day for
women and 171g a day for men) and those who were given advice on healthy snacks
over the period of active weight loss.
The
researchers found that members of the group which ate prunes as part of a
healthy life-style diet lost 2kg in weight and shed 2.5cm off their waists.
However, the people in the group which was given advice on healthy snacks lost
only 1.5kg in weight and 1.7cm from their waists.
The
study also found that the prune eaters experienced greater weight loss during
the last four weeks of the study. After week eight, participants showed
increased feelings of fullness in the prune group. Moreover, despite the high
daily doses, prunes were well tolerated.
Liverpool
psychologist, Dr Jo Harrold who led the research, said: "These are the
first data to demonstrate both weight loss and no negative side effects when
consuming prunes as part of a weight management diet. Indeed in the long term
they may be beneficial to dieters by tackling hunger and satisfying appetite; a
major challenge when you are trying to maintain weight loss."
Professor
Jason Halford, Professor of Experimental Psychology and Director of the
University's Human Ingestive Behaviour Laboratory, added: "Maintaining a
healthy diet is challenging. Along with fresh fruit and vegetables, dried fruit
can provide a useful and convenient addition to the diet, especially as
controlling appetite during dieting can be tough."
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