researchers at illinois explore queen bee longevity

CHAMPAIGN, Ill. — The queen honey bee is genetically identical to the workers in her hive, but she lives 10 times longer and, unlike her sterile sisters, remains reproductively viable throughout life. A study from the University of Illinois sheds new light on the molecular mechanisms that account for this divergence. The study appears in the online edition of the Proceedings of the National Academy of Sciences.

The research centers on the interplay of three factors known to have a role in reproduction, growth and/or longevity. The first, vitellogenin (Vg), is a yolk protein important to reproduction, but which also has been found to contribute to longevity in worker bees. The second, juvenile hormone, contributes to growth and maturation. The third, an insulin-IGF-1 signaling pathway, regulates aging, fertility and other important biological processes in invertebrates and vertebrates.

The study explores these factors in queen honey bees. How, the researchers wanted to know, could the queen achieve such a long life compared with her sisters, while also devoting so much energy to reproduction?

“Many times the way organisms achieve longevity is via a tradeoff with reproduction,” said entomology professor Gene Robinson, principal investigator on the study. “In general, life forms that postpone reproduction until later in life live longer. But the queen bee has her cake and eats it too. She’s an egg-laying machine. She lays 2,000 eggs a day and yet lives 10 times longer than individuals that stem from the same genome and yet do not reproduce.”

The researchers knew from studies of the fruit fly and nematode that the insulin-signaling pathway had a role in longevity. Down-regulation of insulin-IGF-1 signaling (IIS) in those species was associated with increases in longevity, but at the expense of fertility.

They also knew that manipulating fat body cells in the head of the fruit fly influenced longevity. Because Vg is synthesized in fat body cells in honey bees, the team decided to look at Vg expression in the head and thorax, as well as the abdomen.

This led to an important discovery. Expression of Vg was high in the abdomen in the young queen and declined over time, but increased with age in the head and thorax. Old queens showed much higher Vg expression than young queens.

Worker bees had much lower levels of Vg expression than queens, and Vg in worker heads was also low, compared with queens. Previous studies in workers had shown that Vg reduced oxidative stress in honey bees by scavenging free radicals that can lead to aging or illness. Not surprisingly, queens were more resistant to oxidative stress than workers.

Whether this is the actual mechanism by which queens achieve both fertility and long life remains to be seen, Robinson said. In any event, this study suggests that vitellogenin plays a vital role in queen bee longevity, he said, particularly since the honey bee lacks many antioxidants commonly found in other species.

“There are implications here (for other species) in the sense that here is an organism that is reproductively active and long-lived,” said Robinson, who is also affiliated with the Institute for Genomic Biology. “And we see novel and conserved factors that are part of a large regulatory network. The queen has her cake and eats it too. And humans want to know how that works.”


	Entomology professor Gene Robinson is the principal investigator on a study that looked at queen bee longevity. Photo by L. Brian Stauffer

foundation for the preservation of honey bees call for scholarship applications

The Foundation for the Preservation of Honey Bees, Inc. is a charitable research and education foundation affiliated with the American Beekeeping Federation (ABF). The Foundation was created by a generous gift from the Glenn and Gertude Overturf estate and it is sustained by ongoing gifts from ABF members and other supportive individuals. The Foundation Trustees have chosen to use a portion of the grant to offer five $2,000 scholarships to graduate students in apiculture with the stipulation that a portion of the funds be used to attend the 2008 joint meeting of the American Beekeeping Federation, the American Honey Producers Association, the Apiary Inspectors of America and the American Association of Professional Apiculturists in Sacramento, California, January 8-12, to present their research. The Board of Trustees hopes that the scholarships will encourage young apicultural scientists and looks forward to their contributions to the 2008 meeting. The scholarships are available to all graduate students, and students at universities outside the U.S. are invited to apply. Applications for the scholarships will be accepted until August 15, 2007.

Applicants should submit a cover letter from their advisor, a curriculum vitae and a research summary (not to exceed 3 pages) to the Board for consideration. The research summary can cover research completed within the past 2 years or proposed research that will have begun prior to the meeting. Recipients will be selected in September of 2007.

Applications can be submitted electronically or in print. Send scholarship applications to:

Troy H. Fore Jr., Executive Director

Foundation for the Preservation of Honey Bees

P.O. Box 1337, Jesup, GA 31598

Email: troyfore@honeybeepreservation.org

If you have questions or need more information about the scholarship program, contact:

Marion Ellis, Scholarship Program Coordinator

Foundation for the Preservation of Honey Bees

mellis3@unl.edu

A SWEET ALTERNATIVE FOR TREATING DIABETIC ULCERS?

University of Wisconsin study tests topical honey for healing wounds

EAU CLAIRE, WI—The sore on Catrina Hurlburt’s leg simply wouldn’t heal.

Complications from a 2002 car accident left Hurlburt, a borderline diabetic, with recurring cellulitis and staph infections. One of those infections developed into a troublesome open sore that, despite the use of oral antibiotics, continued to fester for nearly eight months.

Then, Hurlburt’s physician, Dr. Jennifer Eddy of UW Health’s Eau Claire Family Medicine Clinic, suggested she try using topical honey.

Within a matter of months, the sore had healed completely.

“I remember thinking, holy mackerel—what a difference,” says Hurlburt, who can’t use topical antibiotics because of allergies. “It’s a lot better than having to put oral antibiotics into your system.”

With funding provided by the Wisconsin Partnership Fund for Health and the American Academy of Family Physicians Foundation, Dr. Eddy is currently conducting the first randomized, double-blind controlled trial of honey for diabetic ulcers. Eddy first successfully used honey therapy a few years ago with a patient who was facing amputation after all medical options had been exhausted.

Experts believe that treating wounds with honey has tremendous potential for the approximately 200 million people in the world with diabetes, 15 percent of whom will develop an ulcer, usually because of impaired sensation in their feet. Currently, every 30 seconds someone somewhere in the world undergoes amputation for a diabetic foot ulcer. In 2001, treating diabetic ulcers and amputations in U.S. patients cost $10.9 billion.

“Patients like Catrina Hurlburt are a great example of the potential health care savings,” explains Eddy, who is also assistant professor of family medicine at University of Wisconsin School of Medicine and Public Health. “Unsuccessful conventional care for ulcers can cost thousands of dollars. Therapy with honey may only cost a few hundred.”

Diabetics typically have poor circulation and decreased ability to fight infection. Diabetic ulcers treated with long courses of systemic antibiotics can become colonized with drug-resistant organisms—so-called “superbugs” such as Methicillin-resistant Staphylococcus aureus (MRSA). Since honey fights bacteria in numerous ways, it is essentially immune to resistance. Honey’s acidic pH, low water content (which effectively dehydrates bacteria), and the hydrogen peroxide secreted by its naturally-occurring enzymes make it ideal for combating organisms that have developed resistance to standard antibiotics.

“This is a tremendously important issue for public health,” explains Eddy, adding that the Centers for Disease Control and the World Health Organization have identified bacterial resistance as one of the most important medical problems of our day.

Patients in the clinical trial will receive ulcer care and treatment by an expert podiatrist. Half will be randomly assigned to receive honey, while the other half will receive a wound-care gel that has been compounded with inert components to give it the flavor and color of honey. The ulcers will be measured to see how quickly they heal, to evaluate whether honey or the standard wound gel is better for healing.

If honey proves the more effective method, Eddy cautions patients against using it at home without a physician’s involvement. “Unfortunately, diabetic ulcers are very complicated, and honey would only be part of the solution,” she says. Successful care also requires off-loading—avoiding walking and putting weight on the sore—and the sterile removal of dead skin and bacteria from the wound.

“If we can prove that honey promotes healing in diabetic ulcers, we can offer new hope for many patients,” says Eddy. “Not to mention the cost benefit, and the issue of bacterial resistance. The possibilities are tremendous.”

To be eligible for the study, patients must be older than 18, have diabetes and a sore below their knee, and not be taking prednisone. Interested patients can call (715) 855-5683 for further information on the study or outreach opportunities. (University of Wisconsin School of Medicine & Public Health)

new bacterium may hold promise for small hive beetle control

A bacterium discovered by Agricultural Research Service (ARS) scientists that is toxic to Colorado potato beetle also has been found to be toxic in varying degrees to gypsy moth, small hive beetle and tobacco hornworm.

Microbiologist Phyllis Martin, molecular biologist Dawn Gundersen-Rindal, and entomologist Michael Blackburn at the ARS Insect Biocontrol Laboratory, Beltsville, Md., and chemist Jeffrey Buyer at the Sustainable Agricultural Systems Laboratory in Beltsville found and described the new bacterial species, Chromobacterium suttsuga, now called Chromobacterium subtsugae sp. nov. The group then found that the bacterium displayed toxicity to Colorado potato beetle.

The findings were published in the May issue of the International Journal of Systematic and Evolutionary Micro-biology.

Soil rich in decomposed hemlock leaves, collected from the Catoctin Mountain region in central Maryland, was the source of the new species. The team isolated the microbe by suspending samples of forest soil in water and then plating it directly on growth medium that doesn’t contain glucose. Bacteria in the samples initially formed small and cream-colored colonies, which gradually turned to light-to-dark violet from the center of the colony outward.

Fifty percent of small hive beetles died within five days when fed a pollen-based diet containing the bacteria, and the survivors weighed only 10 percent as much as small hive beetles that weren’t exposed to the bacteria. Tobacco hornworm and gypsy moth weren’t killed by the bacteria, but their weights were drastically reduced due to feeding inhibition. Weights of tobacco hornworms that were fed the bacteria-laced diet were drastically reduced—24 milligrams for bacteria-treated insects compared to 119 milligrams for insects that didn’t eat the bacteria. Gypsy moths eating the bacteria weighed 40 percent less than gypsy moths that weren’t fed the bacteria.

Martin and her colleagues will work to isolate the toxin from the bacteria. Insects usually develop resistance to toxic substances, so it is important to identify new toxins.

In previous studies conducted by Martin, Chromobacterium subtsugae sp. nov. was also found to be toxic, in varying degrees, to western corn rootworm, southern corn rootworm and diamondback moth.

ARS is the U.S. Department of Agriculture’s chief scientific research agency.

UC Davis rebuilding honey bee program:
bee breeder and geneticist susan cobey joins uc davis team

Intent on meeting the needs of California's multibillion dollar agriculture industry, the University of California, Davis, is revitalizing its honey-bee research program, the oldest such program in the nation.

Once a powerhouse in bee biology research, the UC Davis program declined during the 1990s as faculty retirements and budget shortages collided. With California's honey-bee industry now facing challenges ranging from mites to small hive beetles to colony collapse disorder, rebuilding the 65-year-old program has become critical.

California agriculture produces almonds, alfalfa, sunflowers, tree fruit and many other crops that rely on bees for pollination each spring.

"The honey-bee industry plays a key role in the success of California agriculture, and it is imperative that UC Davis provide the research necessary to help solve some of the pressing problems related to bee health, breeding and pollination," said Neal Van Alfen, dean of the College of Agricultural and Environmental Sciences. "During the coming years we will be adding new staff and faculty to our bee biology program and renovating the Harry Laidlaw Jr. Honey Bee Research Facility here on campus."

One of the first steps toward rebuilding the research program is the hiring of accomplished bee breeder and geneticist Susan Cobey, who has been at The Ohio State University. Cobey arrives this week as full-time manager of the Laidlaw bee biology facility and plans to begin offering specialized classes to bee breeders in May and June.

"It is a huge honor to help revive UC Davis' bee biology laboratory," said Cobey, who worked in the Laidlaw lab during the late 1970s and early 1980s. She was mentored by its namesake, the late Professor Harry Laidlaw, who inspired her career choice. She has gone on to become a leading expert in instrumental insemination of bees and practical bee breeding.

"California is the center for the bee industry and home to some of the nation's best beekeepers," Cobey said. "I look forward to working with them, with an emphasis on stock improvement."

In addition to hiring Cobey, the bee biology program will be further bolstered by:

·The addition of a new professor in UC Davis' entomology department who will specialize in the biology of bee pollination. That position is expected to be filled by late fall, according to Walter Leal, who chairs the entomology department.

·A $500,000 renovation of the 8,200 square foot Laidlaw bee biology facility, which is home to laboratories, offices, an apiarium with glass-walled observation hives, a honey-bee food processing room and shop. The building is being remodeled to include a larger multipurpose room, a walk-in freezer and other facility improvements.

·The establishment of a $1 million endowment fund that will directly support research efforts in the areas of honey-bee genetics and pollination biology. Through the generous support of the estate of Harry and Ruth Laidlaw and contributions from the beekeeping industry, the endowment has already surpassed the $400,000 mark. All of the earnings from this endowment will support graduate students and research projects directly related to honey bees.

For her part, Cobey will focus on strengthening ties between the university research community and the honey-bee industry. She maintains a breeding line of bees known as New World Carniolans, which she developed during the early 1980s, when she was a professional bee breeder and co-owner of Vaca Valley Apiaries in Northern California.

She will collaborate with Cooperative Extension apiculturist Eric Mussen, who has anchored the bee biology program's research and industry education efforts during the lean years. His bee industry leadership and research in the areas of colony management, pollination, mite control and insecticide damage, were recently recognized by the American Association of Professional Apiculturists, which awarded Mussen its Apicultural Excellence Award. Mussen was also the first noncommercial bee producer to receive the prestigious Beekeeper of the Year Award at the 2006 California State Beekeepers Association Conference. (UC Davis News & Information)

almond production sets another record high in 2007

The initial forecast for the 2007 California almond production is 1.31 billion pounds, 17 percent above last year’s revised production of 1.12 billion pounds. January crop year-to-date shipments increased 27% versus the same time period last year, achieving record breaking numbers for domestic and export markets. Domestic shipments are up 23% overall with record monthly shipments in each of the last five months. Export shipments were up 29% from last year. The top five export markets this crop year are Germany, Spain, India, Japan and China, representing 50% of all California almond exports. (National Honey Board Bee Mail, Issue 107)

propolis researched as a food preservative

New research recently suggested that propolis, currently marketed by some for its health benefits, could also find use as a natural food preservative, according to a recent issue of the Food Chemistry journal.

"It may be concluded that, the ethanolic extract of propolis tested, in the performed experimental conditions may successfully inhibit the E. coli development in vitro, at safe levels for human consumption and, consequently, they could be useful as ground fresh beef natural preserver or as unspecific antibacterial food preserver," wrote lead author Enzo Tosi.

Tosi and his co-workers from Argentina's National University of Technology looked at the effect of Argentinian propolis extracts against E.coli, and thereby as a preservative for foods.

"Most propolis components are natural constituents of food and recognized as safe substances," added Tosi. (National Honey Board Bee Mail, Issue 107)

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