- Author: Kathy Keatley Garvey
In research led by postdoctoral researcher Zuodong Zhang, a team of 16 scientists discovered a key mechanism by which dietary omega-3 fatty acids (fish oils) could reduce the tumor growth and spread of cancer, a disease that kills some 580,000 Americans a year.
The research is published today (April 3) in the Proceedings of the National Academy of Sciences (PNAS). They discovered cytochrome P450 epoxygenase metabolites of omega-3 fatty acid DHA or epoxy docosapentaenoic acids (EDPs) block blood supply to the tumor and thus inhibit tumor growth and metastasis.
The natural EDPs were further stabilized by a drug called a soluble epoxide hydrolase inhibitor which is already under development to control pain and hypertension.
“Many human studies have shown that omega-3 fatty acids reduce the risks of cancers, but the mechanism is poorly understood,” said Zhang, a postdoctoral researcher who focuses his research on lipid mediators on angiogenesis, tumor growth and metastasis. “Our study provides a novel mechanism by which these omega-3 lipids inhibit cancer.”
“We demonstrated that EDPs have very potent anti-cancer and anti-metastatic effects,” Zhang said. “Current anti-cancer drugs that block angiogenesis (the formation of new blood vessels to fuel tumor progression) can cause serious side effects such as hypertension. By blocking angiogenesis by a new mechanism and by widening blood vessels, EDPs could block tumor growth with reduced side effects in cancer patients.”
The studies, conducted on mice, also suggest that a combination of omega-3 diet and some anti-cancer drugs such as sorafenib, “could not only be efficacious to treat cancers but reduce potential side effects,” said Zhang, who received his doctorate in food science from the University of Wisconsin-Madison.
“Thus the effects of the soluble epoxide hydrolase inhibitors have opposite effects depending on whether the background lipid mediators are omega 3 or omega 6,” Hammock said. “Assuming that humans are mice (the study involved mice), the prediction is that with some cancer drugs--particularly the ones like sorafenib and regorafenib that are potent epoxide hydrolase inhibitors as well as anti-angiogenic agents--these could be more effective with a high omega 3 and low omega 6 background.”
“This is an exciting step towards our full appreciation of the impact of bioactive products from the DHA metabolome,” said Charles Serhan of Harvard Medical School, an expert on omega-3 autacoids and inflammation who is the Simon Gelman Professor of Anesthesia, Periopterative and Pain Medicine, Harvard Medical School. “This (UC Davis) contribution places metabolic conversion of omega-3 DHA to epoxy DHA products pivotal in vascular mechanisms key in cancer and vascular biology. It will be exciting to watch these important findings translated to humans for new evidence based treatments for angiogenesis, tumor growth and cancer metastasis.”
Said cardiologist Jonathan Lindner of the Oregon Health & Science University: “New drug strategies for fighting cancer could emerge from knowledge of how the body uses nutrition to promote health. Diet has been shown to influence susceptibility to many types of cancer, and also to influence rate of tumor progression and response to chemotherapy. This information has been leveraged to make reasonable recommendations on diet in patients with cancer. Perhaps more importantly, by uncovering how diet influences tumor development and growth, it may be possible to develop new drugs that work through the same beneficial pathways.”
“The study by Zhang and colleagues has uncovered a previously unrecognized anti-cancer effect of omega-3 fatty acids which are an important lipid component of diets that have been developed to prevent heart disease and cancer,” Lindner said. “The authors have demonstrated that metabolites of these lipids can act to suppress the growth of new blood vessels that are necessary to feed tumor growth. By shutting off the tumor’s blood supply, these compounds can act to dramatically slow tumor growth and prevent metastasis. The results from this suggest that new drug strategies for fighting cancer could emerge from knowledge of how the body uses nutrition to promote health.”
Read more about the research on the UC Davis Department of Entomology website and see photos of some of the co-authors.
- Author: Kathy Keatley Garvey
The aphids know how to plan a family reunion.
Grandma, grandpa, aunts, uncles, mom and pop, brothers and sisters, cousins and more cousins--they're all gathering to feed on the lush growth of the spring roses, the juicy shoots, the tender buds. And they multiply. You think rabbits multiply fast? Try aphids.
A telltale sign of their presence: Crumpled white carcasses and leaves coated with sticky honeydew.
A strong blast of water and the aphids are gone.
Well, at least some of them.
We watched a sole ladybug, aka ladybeetle, feasting on an aphid buffet on Easter Sunday. So many aphids, and so much time. All the aphids on her menu were green, but they come in yellow, brown and black, too.
The aphids crawled along the rose stems, bumping their cornicles or tubelike structures into one another, unaware of the looming red predator in their midst.
Until it was too late.
- Author: Kathy Keatley Garvey
He sounded the alarm.
“We need 1.6 million colonies, or two colonies per acre, and California has only about 500,000 colonies that can be used for that purpose,” said Mussen in a news release we posted Feb. 8 on the Department of Entomology website. “We need to bring in a million more colonies but due to the winter losses, we may not have enough bees.”
Those winter losses--still being tabulated--and the resulting fewer bees per hive could spell trouble for almond growers, he said.
He said 2012 was a bad year for bee nutrition.
“Last year was not a good year for honey production in the United States,” Mussen said, “and it could be one of the worst honey production years in the history of nation, although it’s been pretty rough in some of the previous years. Usually when we’re short of nectar, we’re short on pollen, and honey bees need both. So, 2012 was a bad year for bee nutrition.”
The winter of 2012-2013, in general, was bad for bees. In fact, it's never been good since the winter of 2006 with the onset of colony collapse disorder, a mysterious malady characterized by adult bees abandoning the hive, leaving behind the queen bee, brood and food stores.
Bee scientists think CCD is caused by a multitude of factors, includes, pests, pesticides, parasites, diseases, malnutrition and stress. On the average, beekeepers report they're losing one-third of their bees a year.
“We don’t know how many more bees will be lost over the winter,” Mussen told us on Feb. 8. “We consider the winter ending when the weather warms up and the pollen is being brought into the hives.”
“Many, many colonies are not going to make it through the winter. We won’t have as large a bee population as in the past.”
Mussen, a member of the UC Davis Department of Entomology since 1976, knows honey bees. He is a honey bee guru, a global expert on bees. "Have a question about bees? Ask Eric Mussen." This month, especially, he is in great demand as a news source.
The New York Times quoted Mussen in its March 28th article, "Mystery Malady Kills More Bees, Heightening Worry on Farms."
Eric Mussen, an apiculturist at the University of California, Davis, said analysts had documented about 150 chemical residues in pollen and wax gathered from beehives.
"Where do you start?" Dr. Mussen said. "When you have all these chemicals at a sublethal leel how do they react with each other? What are the consequences?"
Experts say nobody knows.
Meanwhile, Mussen spent much of the day today granting news media interviews. On Tuesday, April 2, it will be for Dan Rather Reports: Buzzkill.
It was not so long ago that honey bees drew little attention, despite the fact that they pollinate about one-third of the food we eat. A three-letter acronym, CCD, changed all that.
Rich Schubert, a beekeeper in the Winters/Vacaville area, said it best during a question-and-answer session at Mussen's UC Davis Distinguished Seminar on Oct. 9, 2007.
If 5600 dead cows were found in a pasture, instead of 5600 dead bees, people would start paying attention, Schubert told the crowd.
So true. And now they are.
- Author: Kathy Keatley Garvey
Insects outnumber us on this earth.
And they always will. By the millions.
Penny Gullan and and Peter Cranston, emeritus professors of entomology at the University of California, Davis, wrote in their textbook, The Insects (Wiley Blackwell) that "Although there are millions of kinds of insects, we do not know exactly (or even approximately) how many. This ignorance of how many organisms we share our planet with is remarkable considering that astronomers have listed, mapped and uniquely identified a comparable diversity of galactic objects. Some estimates...imply that the species richness of insects is so great that, to a near approximation, all organisms can be considered insects."
So it's good to see that when the website,Twisted Sifter, recently chose "The 50 Most Perfectly Timed Photos Ever," three of them were insects.
One insect photo, which they numbered No. 18 (photo by Tustel Ico) depicted a praying mantis on a bicycle. Another, No. 22, showed an unusual bee sting (taken by yours truly) and the third, No. 46, was of a ladybug by Lentilcia on deviantART.
The bee sting photo, which has gone around the world and back, is of Extension apiculturist Eric Mussen of the UC Davis Department of Entomology getting stung in the apiary of the Harry H. Laidlaw Jr. Honey Research Facility. You can see a trail of the bee's abdominal tissue as the bee tries to pull away.
At the time, we were walking through the apiary when he said "Kathy, get your camera ready. The bee's going to sting me." (See Bug Squad entry.) The bee was defending its hive, which is what bees do.
Mussen, with the Department of Entomology since 1976, plans to retire in June of 2014, but like the Energizer bunny, this photo of the bee sting will probably keep on going.
It went from winning a feature photo contest sponsored by the Association for Communication Excellence (ACE), an international association of communicators, educators and information technologists, to being named the Huffington Post's "Most Amazing Photos of 2012"; one of the Sacramento Bee's top 10 news stories of 2012; and My Science Academy's top photos of the year. Along the way, scores of websites named it "Picture of the Day." It also will appear in a number of books.
It's definitely the bee sting felt around the world.
- Author: Kathy Keatley Garvey
Honey bees favor assorted plants, including lavenders, mints, salvias, asters, borage, wild roses, echiums, clover, fireweed, goldenrod and phacelia, but have you ever seen them on a Japanese maple?
Our Japanese maple is flowering in our backyard, a fact that has not gone unnoticed by the honey bees. The colorful tree, (Acer palmatum), coveted for its colorful red leaves, stretches over our fish pond, providing a little shade for the goldfish.
I took this photo in the late afternoon with a Nikon D800 camera and a 200mm macro lens. The 36-megapixel camera swallows up a lot of real estate, and the 200mm lens is perfect for skittish insects.
The honey bees weren't skittish but the long lens did prove handy. It enabled me to photograph the bees without falling into the pond.
