An Apple or Pear a Day May Keep Strokes Away

Apples and pears may keep strokes away. That’s the conclusion of a Dutch study published in Stroke: Journal of the American Heart Association in which researchers found that eating a lot of fruits and vegetables with white flesh may protect against stroke.

While previous studies have linked high consumption of fruits and vegetables with lower stroke risk, the researchers’ prospective work is the first to examine associations of fruits and vegetable color groups with stroke.

The color of the edible portion of fruits and vegetables reflects the presence of beneficial phytochemicals such as carotenoids and flavonoids.

Researchers examined the link between fruits and vegetable color group consumption with 10-year stroke incidence in a population-based study of 20,069 adults, with an average age of 41. The participants were free of cardiovascular diseases at the start of the study and completed a 178-item food frequency questionnaire for the previous year.

Fruits and vegetables were classified in four color groups:

  • Green, including dark leafy vegetables, cabbages and lettuces
  • Orange/Yellow, which were mostly citrus fruits
  • Red/Purple, which were mostly red vegetables
  • White, of which 55 percent were apples and pears

 

During 10 years of follow-up, 233 strokes were documented. Green, orange/yellow and red/purple fruits and vegetables weren’t related to stroke. However, the risk of stroke incidence was 52 percent lower for people with a high intake of white fruits and vegetables compared to people with a low intake.

Each 25 gram per day increase in white fruits and vegetable consumption was associated with a 9 percent lower risk of stroke. An average apple is 120 grams.

“To prevent stroke, it may be useful to consume considerable amounts of white fruits and vegetables,” said Linda M. Oude Griep, M.Sc., lead author of the study and a postdoctoral fellow in human nutrition at Wageningen Uninversity in the Netherlands. “For example, eating one apple a day is an easy way to increase white fruits and vegetable intake.

“However, other fruits and vegetable color groups may protect against other chronic diseases. Therefore, it remains of importance to consume a lot of fruits and vegetables.”

Apples and pears are high in dietary fiber and a flavonoid called quercetin. In the study, other foods in the white category were bananas, cauliflower, chicory and cucumber.

Potatoes were classified as a starch.

Previous research on the preventive health benefits of fruits and vegetables focused on the food’s unique nutritional value and characteristics, such as the edible part of the plant, color, botanical family and its ability to provide antioxidants.

U.S. federal dietary guidelines include using color to assign nutritional value. The U.S. Preventive Health Services Taskforce recommends selecting each day vegetables from five subgroups: dark green, red/orange, legume, starchy and other vegetables.

Before the results are adopted into everyday practice, the findings should be confirmed through additional research, Oude Griep said. “It may be too early for physicians to advise patients to change their dietary habits based on these initial findings,” she said.

An accompanying editorial notes that the finding should be interpreted with caution because food frequency questionnaires may not be reliable.

In addition, “the observed reduction in stroke risk might further be due to a generally healthier lifestyle of individuals consuming a diet rich in fruits and vegetables,” writes Heike Wersching, M.D., M.Sc., of Institute of Epidemiology and Social Medicine at the University of Münster, in Germany.

 

Reference 

Griep LM, Verschuren WM, Kromhout D, Ocké MC, Geleijnse JM. Raw and processed fruit and vegetable consumption and 10-year stroke incidence in a population-based cohort study in the Netherlands. Eur J Clin Nutr 2011; 65 (7): 791-9.

 

More Evidence That Spicing Up Broccoli Boosts Its Cancer-Fighting Power

Teaming fresh broccoli with a spicy food that contains the enzyme myrosinase significantly enhances each food’s individual cancer-fighting power and ensures that absorption takes place in the upper part of the digestive system where you’ll get the maximum health benefit, suggests a new University of Illinois study.

“To get this effect, spice up your broccoli with broccoli sprouts, mustard, horseradish, or wasabi. The spicier, the better; that means it’s being effective,” said Elizabeth Jeffery, a U of I professor of nutrition.

In the study, when fresh broccoli sprouts were eaten with broccoli powder, the scientists were able to measure bioactive compounds in the blood 30 minutes later. When these peaked at three hours, they were much higher when the foods were eaten together than when either was eaten alone. Urine samples corroborated the blood results, said Jenna Cramer, lead author of the study.

It’s no secret that many people cook the benefits right out of broccoli instead of steaming it lightly for two to four minutes to protect its healthful properties, she said.

“However, this study shows that even if broccoli is overcooked, you can still boost its benefits by pairing it with another food that contains myrosinase,” she said.

Myrosinase is the enzyme necessary to form sulforaphane, the vegetable’s cancer-preventive component, co-author Margarita Teran-Garcia explained.

Note what happened with the fresh broccoli sprouts and broccoli powder eaten in this experiment. The powder doesn’t contain myrosinase, but it does contain the precursor to the anti-cancer agent sulforaphane. Eaten together, the sprouts were able to lend their myrosinase to the powder. As predicted, both foods produced sulforaphane and provided greater anti-cancer benefit, Jeffery said.

Other foods that will boost broccoli’s benefits if they are paired together include radishes, cabbage, arugula, watercress, and Brussels sprouts.

“Here’s another benefit of protecting and enhancing the myrosinase in your foods,” Jeffery said. “If myrosinase is present, sulforaphane is released in the ilium, the first part of your digestive system. Absorption happens well and quickly there, which is why we saw bioactivity in 30 minutes.”

An earlier Jeffery study showed that microbiota are capable of releasing sulforaphane in the lower gut, but absorption happens more slowly in the colon than in the upper intestine, she said.

Scientists say that as little as three to five servings of broccoli a week provide a cancer-protective benefit.

“But it pays to spice it up for added benefits and find ways to make it appealing so you don’t mind eating it if you’re not a broccoli fan. I add fresh broccoli sprouts to sandwiches and add them as one of my pizza toppings after the pie is out of the oven,” Cramer said.

 

Reference

Cramer JM, Teran-Garcia M, Jeffery EH. Enhancing sulforaphane absorption and excretion in healthy men through the combined consumption of fresh broccoli sprouts and a glucoraphanin-rich powder.  Br J Nutr. 2011 Sep 13:1-6. [Epub ahead of print].

 

Role Of Soy In Menopausal Health Reported

Discussion of a scientific review of soy protein, soy isoflavones and soy metabolites for peri- and postmenopausal women at North American Menopause Society (NAMS)/Wulf H. Utian Translational Science Symposium:

 

Soy has recently been reviewed and supported for introduction into general medical practice as a treatment for distressing vasomotor symptoms of menopause, such as hot flashes, but its use in other medical areas, such as heart health, requires further research, according to a new report reviewing the risks and benefits of soy protein, isoflavones and metabolites in menopausal health from The North American Menopause Society (NAMS)/Wulf H. Utian Translational Science Symposium, published in the July Menopause, the peer-reviewed NAMS journal.

“Although a significant amount of scientific research about soy and soy isoflavones exists, the adoption of soy isoflavones into the care of women in menopause has to date been recommended mainly by physicians and health care practitioners involved in integrative medicine. We believed that facilitating a robust review of the current scientific evidence about the benefits and risks of soy could yield a document useful to physicians to help them make decisions about soy use with their patients, particularly those in menopause,” said Belinda H. Jenks, Ph.D., director of Scientific Affairs & Nutrition Education at Pharmavite LLC. Otsuka Pharmaceutical Co., Ltd., Pharmavite LLC and the Allmen Foundation supported the development of the symposium and report via an unrestricted educational grant.

The report focuses on a review of soy’s mechanism of action and processing within the body (bioavailability and pharmacokinetics), as well as on several therapeutic areas, concluding that use of soy isoflavones for hot flashes is reasonable and that soy food consumption is associated with lower risk of breast and endometrial cancer. The report also recommended more research to further characterize the effects of soy isoflavones on bone and cardiovascular health as well as cognition, which involves thinking, reasoning, or remembering.

The report, approved by the NAMS Board of Trustees, was authored by 22 clinicians and well-respected scientific research experts in women’s health and botanicals who participated in the symposium in October 2010. They examined basic and clinical research findings from more than two hundred key published controlled trials as well as laboratory studies of the soy isoflavones genistein and daidzein and the daidzein metabolite, S-equol. A supplement containing Natural S-equol for the management of menopausal symptoms is in development by Pharmavite LLC, the makers of Nature Made® vitamins and minerals and a subsidiary of Otsuka Pharmaceutical Co., Ltd.

About Soy Isoflavones and S-Equol

Soy isoflavones are compounds that can bind to estrogen receptors. The isoflavones genistein and daidzein are primarily found in whole soybeans and soy products. S-equol [7-hydroxy-3-(4′-hydroxyphenyl)-chroman] is a compound resulting — when certain bacteria are present in the digestive tract — from the metabolism, or conversion, of daidzein.

S-equol binds to the same estrogen receptors as naturally occurring, endogenous estrogen, but with a stronger affinity for the estrogen beta receptor. On binding to these receptors, S-equol mimics some, but not all, activities of endogenous estrogen. Because of these actions, it has been proposed that S-equol alleviates some of the symptoms caused by diminished estrogen production during menopause.

However, not everyone can produce S-equol after soy consumption, as the production depends on the types of bacteria present in the large intestine and may be influenced by the amount of soy consumed. About 50 percent of Asians and 20 to 30 percent of North Americans and Europeans, who in general consume less soy than Asians, have the ability to produce high levels of S-equol. Controlled clinical trials have documented that a supplement containing Natural S-equol reduces the frequency of hot flashes as well as muscle discomfort associated with menopause, in women both in Japan and the United States.

Soy Isoflavone Bioavailability and Pharmacokinetics

Not all soy foods or supplements contain the same amount or percentage of the three primary isoflavones genistein, daidzein or glycetein. Soyfoods and supplements can vary in soy isoflavone amounts and forms which, in turn, may impact the way the body will metabolize the isoflavones and subsequently can impact their effectiveness in health care, the report states.

For example, the rates of absorption in the body of the isoflavones daidzein and genistein depend on their form. As glycosides, which have an attached sugar molecule, both isoflavones can reach a peak plasma concentration in four to 10 hours. However, the human body cannot use this form, and during digestion the sugar is removed. This resulting aglycone form can be absorbed faster. When consumed as aglycosides, both daidzein and genistein can achieve peak concentrations in just one hour, or up to three hours if eaten with a meal. When the daidzein metabolite S-equol is consumed, its peak plasma rate rapidly occurs in just one to two hours.

The time needed for the total plasma concentration of either isoflavone to decrease by half typically is six to 12 hours and for S-equol, six to eight hours. However, genistein takes significantly longer to leave the body than daidzein. S-equol is excreted almost exclusively in urine, with 75 percent excreted within 12 hours after consumption.

Soy-isoflavones Reasonable for Menopausal Symptoms

The NAMS report advises that in postmenopausal women with distressing vasomotor symptoms, such as hot flashes, initial treatment with soy isoflavones is reasonable because of demonstrated modest effectiveness in early post-menopausal women who have at least four hot flashes daily. The report recommends a starting dose of 50 milligrams (mg) or more daily for at least 12 weeks. If a woman responds, the treatment can continue with monitoring for side effects, but for women who do not respond after 12 weeks, other treatment options should be discussed, the authors suggest.

However, the report points to increasing evidence that women whose gut bacteria have little or no capacity to covert daidzein to S-equol may continue to suffer from severe hot flashes despite daidzein supplementation. The report suggests that dietary supplements providing higher proportions of genistein or S-equol may provide more relief of menopausal symptoms than the modestly effective relief recognized by soy isoflavones alone. Also, the report recommends a supplement containing natural S-equol may be effective for some women who do not have the capacity to produce S-equol, which occurs only when certain bacteria are present in the digestive tract.

The authors’ menopause symptom treatment recommendations were based on a review of 14 studies that included data on soy isoflavone content and dosing, at least 12 weeks of treatment, women who experienced natural (not induced) menopause and the women’s average age, their prevalence of hot flashes at study start and their magnitude of symptom improvement.

Potential Protection for Breast and Endometrial Cancer

Soy foods, in populations that typically consume them, appear to protect against breast cancer. Therefore, the NAMS report advises that moderate life-long dietary soy consumption is recommended as part of a healthy lifestyle. The best evidence indicates that there are no adverse effects from this diet and it has potential for prevention of breast and endometrial cancer, the report states.

However, the authors note that specific recommendations regarding soy food or soy isoflavone consumption by breast cancer survivors cannot be made at this time, although such studies in humans indicate either no effect or a protective effect, but in contrast laboratory and rodent studies indicate a potential for risk.

The authors recommend studies of endometrial risk should focus on long-term, postmenopausal exposures to soy. The authors’ breast and endometrial cancer recommendations were based on a review of at least 18 studies.

 

Further Research about Soy Effects on Women’s Health

The NAMS report identifies several areas for further research on soy in midlife women. Specifically, the authors call for more studies that compare outcomes among women whose intestinal bacteria have the ability to convert daidzein to S-equol with those that do not to determine if equol producers derive greater benefits from soy supplementation. Also, larger studies are needed in younger postmenopausal women, as is more research to understand soy isoflavone supplement use in women. The authors also propose studies on the relationships of other dietary components as well as prescription and over-the-counter medications on soy isoflavones, consumed as a part of the diet or as a supplement, and S-equol production. And finally, the authors request greater standardization and documentation of clinical trial data regarding soy.

 

References

North American Menopause Society. The role of soy isoflavones in menopausal health: report of The North American Menopause Society/Wulf H. Utian Translational Science Symposium in Chicago, IL (October 2010). Menopause 2011; 18 (7): 732-53.

Natural S-equol. A scientific advancement for menopause therapy.

 

Breast Cancer Risk Drops When Diet Includes Walnuts

The risk of breast cancer dropped significantly in mice when their regular diet included a modest amount of walnut, Marshall University researchers report in the journal Nutrition and Cancer.

The study, led by Elaine Hardman, Ph.D., of Marshall’s Joan C. Edwards School of Medicine, compared the effects of a typical diet and a diet containing walnuts across the lifespan: through the mother from conception through weaning, and then through eating the food directly. The amount of walnut in the test diet equates to about 2 ounces a day for humans.

Hardman said that during the study period, the group whose diet included walnut at both stages developed breast cancer at less than half the rate of the group with the typical diet. In addition, the number of tumors and their sizes were significantly smaller.

“These reductions are particularly important when you consider that the mice were genetically programmed to develop cancer at a high rate,” Hardman said. “We were able to reduce the risk for cancer even in the presence of a preexisting genetic mutation.”

The paper notes that dietary modification studies do not show whether benefits result from what is added to a diet or what is removed. In this case, adding healthy fat and other components meant that unhealthy fat was reduced to keep total dietary fat balanced in the mice. Hardman said other studies have clearly shown, however, that multiple ingredients in walnuts reduce the risk of cancer or slow its growth.

Using genetic analysis, the Marshall study found that the walnut-containing diet changed the activity of multiple genes that are relevant to breast cancer in both mice and humans. Other testing showed that increases in omega 3 fatty acids did not fully account for the anti-cancer effect, and found that tumor growth decreased when dietary vitamin E increased.

Hardman said the findings highlight the vital role diet plays in health.

“Food is important medicine in our diet,” she said. “What we put into our bodies makes a big difference – it determines how the body functions, our reaction to illness and health. The simple stuff really works: eat right, get off the couch, and turn off the TV.

“The results of this study indicate that increased consumption of walnut could be part of a healthy diet and reduce risk for cancer in future generations,” she said.

The study was funded by grants from the American Institute for Cancer Research and the California Walnut Commission.

 

Reference

Hardmana WE, Iona G, Akinsete JA, Witte TR. Dietary Walnut Suppressed Mammary Gland Tumorigenesis in the C(3)1 TAg Mouse. Nutrition and Cancer 2011; 63 (6): 960-970.

 

 

It’s Official — Chocolate Linked To Heart Health

Chocolate consumption and cardiometabolic disorders: systematic review and meta-analysis.

High levels of chocolate consumption might be associated with a one third reduction in the risk of developing heart disease, finds a study published on bmj.com.

The findings confirm results of existing studies that generally agree on a potential beneficial link between chocolate consumption and heart health. However, the authors stress that further studies are now needed to test whether chocolate actually causes this reduction or if it can be explained by some other unmeasured (confounding) factor.

The World Health Organisation predicts that by 2030, nearly 23.6 million people will die from heart disease. However, lifestyle and diet are key factors in preventing heart disease, says the paper.

A number of recent studies have shown that eating chocolate has a positive influence on human health due to its antioxidant and anti-inflammatory properties. This includes reducing blood pressure and improving insulin sensitivity (a stage in the development of diabetes).

However, the evidence about how eating chocolate affects your heart still remains unclear. So, Dr Oscar Franco and colleagues from the University of Cambridge carried out a large scale review of the existing evidence to evaluate the effects of eating chocolate on cardiovascular events like heart attack and stroke.

They analysed the results of seven studies, involving over 100,000 participants with and without existing heart disease. For each study, they compared the group with the highest chocolate consumption against the group with the lowest consumption. Differences in study design and quality were also taken into account to minimise bias.

Five studies reported a beneficial link between higher levels of chocolate consumption and the risk of cardiovascular events and they found that the “highest levels of chocolate consumption were associated with a 37% reduction in cardiovascular disease and a 29% reduction in stroke compared with lowest levels.” No significant reduction was found in relation to heart failure.

The studies did not differentiate between dark or milk chocolate and included consumption of chocolate bars, drinks, biscuits and desserts.

The authors say the findings need to be interpreted with caution, in particular because commercially available chocolate is very calorific (around 500 calories for every 100 grams) and eating too much of it could in itself lead to weight gain, risk of diabetes and heart disease.

However, they conclude that, given the health benefits of eating chocolate, initiatives to reduce the current fat and sugar content in most chocolate products should be explored.

 

Reference

Buitrago-Lopez A, Sanderson J, Johnson L, Warnakula S, Wood A, Di Angelantonio E, Franco OH. Chocolate consumption and cardiometabolic disorders: systematic review and meta-analysis. BMJ 2011; 343: d4488.

 

Research Shows Heat In Chili Peppers Can Ease Sinus Problems

Hot chili peppers are known to make people “tear up,” but a new study led by University of Cincinnati allergy researcher Jonathan Bernstein, MD, found that a nasal spray containing an ingredient derived from hot chili peppers (Capsicum annum) may help people “clear up” certain types of sinus inflammation.

The study, which appears in the August 2011 edition of Annals of Allergy, Asthma & Immunology, compares the use of the Capsicum annumnasal spray to a placebo nasal spray in 44 subjects with a significant component of no nallergic rhinitis (i.e., nasal congestion, sinus pain, sinus pressure) for a period of two weeks.

Capsicum annum contains capsaicin, which is the main component of chili peppers and produces a hot sensation. Capsaicin is also the active ingredient in several topical medications used for temporary pain relief. It is approved for use by the U.S. Food and Drug Administration and is available over the counter.

“Basically, we concluded that the spray was safe and effective on non-allergic rhinitis,” Bernstein says of the study which showed that participants who used a nasal spray with Capsicum reported a faster onset of action or relief, on average within a minute of using the spray, than the control group.

Non-allergic rhinitis is an upper respiratory condition not caused by allergies but instead caused by environmental factors such as weather, household chemicals or perfumes; however, there are some people who have no triggers or don’t know what triggers are causing the inflammation, Bernstein says.

This is the first controlled trial where capsaicin was able to be used on a continuous basis to control symptoms. It is considered a significant advance, “because we don’t really have good therapies for non-allergic rhinitis,” says Bernstein, adding that in previous trials the ingredient was too hot to administer without anesthesia.

 

Reference 

Bernstein JA, Davis BP, Picard JK, Cooper JP, Zheng S, Levin LS. A randomized, double-blind, parallel trial comparing capsaicin nasal spray with placebo in subjects with a significant component of nonallergic rhinitis. Ann Allergy Asthma Immunol 2011; 107 (2): 171-8.

 

Chocolate Is A ‘Super Fruit’

It is widely known that fruit contains antioxidants which may be beneficial to health. New research published in the open access journalChemistry Central Journal demonstrates that chocolate is a rich source of antioxidants and contains more polyphenols and flavanols than fruit juice.

When researchers at the Hershey Center for Health & Nutrition™ compared the antioxidant activity in cocoa powder and fruit powders they found that, gram per gram, there was more antioxidant capacity, and a greater total flavanol content, in the cocoa powder.

Similarly when they compared the amount of antioxidants, per serving, of dark chocolate, cocoa, hot chocolate mix and fruit juices they found that both dark chocolate and cocoa had a greater antioxidant capacity and a greater total flavanol, and polyphenol, content than the fruit juices. However hot chocolate, due to processing (alkalization) of the chocolate, contained little of any.

Dr Debra Miller, the senior author of the paper, says that, “Cacao seeds are a “Super Fruit” providing nutritive value beyond that of their macronutrient composition”. Which is great news for chocolate lovers.

 

Reference

Crozier SJ, Preston AG, Hurst JW, Payne MJ, Mann J, Hainly L, Miller DL. Cacao seeds are a “Super Fruit”: A comparative analysis of various fruit powders and products. Chemistry Central Journal 2011, 5: 5.

 

Coriander Oil Could Tackle Food Poisoning And Drug-Resistant Infections

Coriander oil has been shown to be toxic to a broad range of harmful bacteria. Its use in foods and in clinical agents could prevent food-borne illnesses and even treat antibiotic-resistant infections, according to the authors of a study published in the Journal of Medical Microbiology.

The researchers from the University of Beira Interior in Portugal tested coriander oil against 12 bacterial strains, including Escherichia coli, Salmonella enterica, Bacillus cereus and meticillin-resistant Staphylococcus aureus (MRSA). Of the tested strains, all showed reduced growth, and most were killed, by solutions containing 1.6% coriander oil or less.

Coriander is an aromatic plant widely used in Mediterranean cuisine. Coriander oil is one of the 20 most-used essential oils in the world and is already used as a food additive. Coriander oil is produced from the seeds of the coriander plant and numerous health benefits have been associated with using this herb over the centuries. These include pain relief, ease of cramps and convulsions, cure of nausea, aid of digestion and treatment of fungal infections.

This study not only shows that coriander oil also has an antibacterial effect, but provides an explanation for how it works, which was not previously understood. “The results indicate that coriander oil damages the membrane surrounding the bacterial cell. This disrupts the barrier between the cell and its environment and inhibits essential processes including respiration, which ultimately leads to death of the bacterial cell,” explained Dr Fernanda Domingues who led the study.

The researchers suggest that coriander oil could have important applications in the food and medical industries. “In developed countries, up to 30% of the population suffers from food-borne illness each year. This research encourages the design of new food additives containing coriander oil that would combat food-borne pathogens and prevent bacterial spoilage,” said Dr Domingues. “Coriander oil could also become a natural alternative to common antibiotics. We envisage the use of coriander in clinical drugs in the form of lotions, mouth rinses and even pills; to fight multidrug-resistant bacterial infections that otherwise could not be treated. This would significantly improve people’s quality of life.”

 

Reference

Silva F, Ferreira S, Duarte A, Mendonça DI, Domingues FC. Antifungal activity of Coriandrum sativum essential oil, its mode of action against Candida species and potential synergism with amphotericin B. Phytomedicine. 2011 Jul 23. [Epub ahead of print].

 

No Bones About It: Eating Dried Plums 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.

Bahram Arjmandi is Florida State's Margaret A. Sitton Professor and chairman of the Department of Nutrition, Food and Exercise Science. Photo: FSU Photography Services

“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 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.”

 

Researchers Demonstrate Green Tea Compound Is Effective In Treating Genetic Disorder And Two Types Of Tumors

A compound found in green tea shows great promise for the development of drugs to treat two types of tumors and a deadly congenital disease.  The discovery is the result of research led by Principal Investigator, Dr. Thomas Smith at The Donald Danforth Plant Science Center and his colleagues at The Children’s Hospital of Philadelphia. Their findings are published in the recent article, “Green Tea Polyphenols Control Dysregulated Glutamate Dehydrogenase In Transgenic Mice By Hijacking The ADP Activation Site” in The Journal of Biological Chemistry.

Shown here is a ribbon diagram of glutamate dehydrogenase with each of the identical subunits represented in different colors. The orange spheres represent the substrate and the yellow spheres denote the location of the green tea compounds bound to the enzyme. The background is of a tea plantation in India.

Glutamate dehydrogenase (GDH) is found in all living organisms and is responsible for the digestion of amino acids. In animals, GDH is controlled by a complex network of metabolites. For decades it was not clear why animals required such regulation but other kingdoms did not.  This was partially answered by the Stanley group’s finding that a deadly congenital disease, hyperinsulinism/hyperammonemia (HHS), is caused by the loss of some of this regulation. In this disorder, patients (typically children) respond to the consumption of protein by over secreting insulin, becoming severely hypoglycemic, often leading to death.

Using atomic structures to understand the differences between animals and plants, Dr. Smith and his colleagues discovered that two compounds found naturally in green tea are able to compensate for this genetic disorder by turning off GDH in isolated and when the green tea compounds were administered orally. The Smith lab also used X-ray crystallography to determine the atomic structure of these green tea compounds bound to the enzyme. With this atomic information, they hope to be able to modify these natural compounds to design and develop better drugs.

Interestingly, two other research groups have validated and extended these findings to demonstrate that blocking GDH with green tea is very effective at killing two different kinds of tumors; glioblastomas, an aggressive type of brain tumor, and tuberous sclerosis complex disorder, a genetic disease that causes non-malignant tumors to grow on a number of organs.

Shown here is a surface representation of glutamate dehydrogenase (GDH) with each of the six identical subunits represented by different colors. Also shown is the location of ECG, a major compound found in green tea. From this structure, it appears that ECG inhibits GDH by binding to the back of the active site and forcing it open. This effectively shuts the enzyme down. Our other studies have shown that these green tea compounds are effective at shutting down the enzyme in tissue and in whole animals. This not only treats a deadly congenital disorder but is also useful in treating at least two types of tumors.

“While these compounds from green tea are extremely safe and consumed by millions every day, they have a number of properties that make them difficult to use as actual drugs. Nevertheless, our ongoing collaboration with the Stanley lab shows that there are natural compounds from plants that can control this deadly disorder and, with the atomic structure in hand, can be used as a starting point for further drug design.”

 

About The Donald Danforth Plant Science Center

Founded in 1998, the Donald Danforth Plant Science Center is a notforprofit research institute with a mission to improve the human condition through plant science. Research at the Danforth Center will feed the hungry and improve human health, preserve and renew the environment, and enhance the St. Louis region and Missouri as a world center for plant science. The Center’s work is funded through competitive grants and contract revenue from many sources, including the National Institutes of Health, U.S. Department of Energy, National Science Foundation, U.S. Department of Agriculture, U.S. Agency for International Development, the Bill & Melinda Gates and Howard G. Buffett Foundations.