Animal studies examine role of raspberry products in weight management and motor function

 

The latest issue of the Journal of Berry Research includes two new animal studies that investigate the effects of raspberry consumption in helping to support healthy weight and motor function (strength, balance and coordination). Future studies are needed to support the results found in these studies.

One-cup of frozen red raspberries has only 80 calories, is an excellent source of vitamin C, and provides nine grams of fiber (more fiber than any other berry). Like most berries, raspberries are a low-glycemic index food. Raspberries contain phytochemicals, such as ellagic acid, quercetin, gallic acid, cyanidins, pelargonidins, catechins, kaempferol and salicylic acid.

Animal and cellular studies examining how phytochemicals may work at the molecular level suggest that certain phytochemicals may help slow age-related declines. Age is the number one risk factor for many chronic diseases. Likewise, obesity is a major risk factor for chronic disease. These latest animal studies examine two important areas of health where raspberry products may play a role in weight management and also support motor function.

OBESITY

An animal study conducted by researchers at Oregon State University found that when added to a high-fat, high-sucrose diet, raspberry products and raspberry phytochemicals were found to significantly decrease weight gain associated with a high-fat, high calorie diet. Raspberry juice and raspberry puree concentrates were provided at 10% of total energy (the equivalent of 200 calories in a 2,000 calorie diet), and a combination of ellagic acid and raspberry ketone were provided at 0.2% weight/weight.

In the study, 76 male mice were divided into the following diets: a low-fat control group (10% calories from fat), a high-fat control group (45% calories from fat) and seven "high-fat treatment" groups that included a high-fat diet plus either raspberry juice concentrate, raspberry puree concentrate, raspberry fruit powder, raspberry seed extract, raspberry ketone and a combination of equal parts of ellagic acid and raspberry ketone.

"The addition of raspberry juice concentrate, raspberry puree concentrate and the combination of ellagic acid plus raspberry ketones to the high fat diet significantly reduced weight gain observed in the high-fat fed mice," said Dr. Neil Shay, Principal Investigator. "In the case of the high-fat and raspberry juice concentrate diet, weight gain was reduced to a level that was statistically equivalent to the weight gain of the low-fat fed mice, despite the fact that all high-fat fed groups consumed the same amount of calories and more energy than the low-fat control group throughout the study."

The researchers concluded that the intake of a reasonable level of some raspberry food products may influence some of the metabolic consequences of consuming a high-fat, high-calorie diet in the development of obesity in male mice.

"We hope that the findings from this study can help guide the design of future clinical trials," said Dr. Shay.

MOTOR FUNCTION

Researchers from the Human Nutrition Research Center on Aging at Tufts University evaluated the effectiveness of a red raspberry-supplemented diet on age-sensitive measures of learning, memory and motor performance in older rats.

In this 10-week study, red raspberry supplementation was found to significantly improve motor skills. Specifically, compared to rats fed a standard well-balanced diet, rats fed a diet supplemented with freeze-dried raspberry extract performed better on tests which measured psychomotor coordination and balance, as well as tests that measure muscle tone, strength, and stamina.

"These results may have important implications for healthy aging," said lead researcher Barbara Shukitt-Hale, PhD. "While further research in humans is necessary, animal model studies are helpful in identifying deficits associated with normal aging."

Mouse study finds black raspberries can prevent colorectal cancer

We know that, The blackberries, as well as various other Rubus species with mounding or rambling growth habits, are often called brambles. However, this name is not used for those like the raspberry that grow as upright canes, or for trailing or prostrate species such as most dewberries, or various low-growing boreal, arctic, or alpine species. Black raspberries have been also reported to possess antioxidant, anti-cancer, anti-neurodegenerative and anti-inflammatory properties, now the researchers from UIC College of Medicine have looked at the fruit's ability to prevent colon cancer.

The researchers used two strains of mice, Apc1638 and Muc2, which each have a specific gene knocked out, causing the mice to develop either intestinal tumors (in the case of Apc1638) or colitis in the case of Muc2. Colitis is an inflammation of the large intestine that can contribute to the development of colorectal cancer.

Both mouse strains were randomized to be fed either a Western-style, high-risk diet (high in fat and low in calcium and vitamin D) or the same diet supplemented with 10 percent freeze-dried black raspberry powder for 12 weeks.

The researchers found that in both mouse strains the black raspberry-supplemented diet produced a broad range of protective effects in the intestine, colon and rectum and inhibited tumor formation.

In the Apc1638 mice, tumor incidence was reduced by 45 percent and the number of tumors by 60 percent. The researchers found that black raspberries inhibited tumor development by suppressing a protein, known as beta-catenin, which binds to the APC gene.

In the Muc2 mice, tumor incidence and the number of tumors were both reduced by 50 percent, and black raspberries inhibited tumor development by reducing chronic inflammation associated with colitis.

The researchers now hope to obtain funding to begin clinical trials in humans. Because black raspberries not only prevent cancer but also inflammation, they may also protect against other diseases, such as heart disease.

I read an article in the same lines, wherein the researchers attribute the colorectal anticancer activity due to the anthocyanins present

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