A leading global scientist and inventor in the field of insect olfaction and communication, Leal was elected an NAI Fellow in 2019 for his impact in the fields of molecular, cellular biology, and entomology, but due to the COVID pandemic, the organization cancelled the 2020 Phoenix ceremony. Travel restrictions prevented him from attending the 2021 ceremony in Tampa, Fla. Elected Fellows are required to attend the induction ceremony within two years of election in order to receive their award.
NAI singles out outstanding inventors for their “highly prolific spirit of innovation in creating or facilitating outstanding inventions that have made a tangible impact on the quality of life, economic development, and welfare of society.” Election to NAI Fellow is the highest professional distinction accorded solely to academic inventors. The NAI Fellow program has 1,403 Fellows worldwide representing more than 250 prestigious universities and governmental and non-profit research institutes.
“I attended with my wife, Beatriz, and daughter Helena and son Gabriel – both have co-authored papers in the lab, so they represent all visiting scholars, collaborators, postdocs, project scientists, graduate students, and undergraduate students in my lab,” Leal said. (See video of the awarding of the medals)
UC Davis chancellor emerita Linda Katehi, an NAI fellow inducted in 2012, nominated Leal for the honor for his “novel, sustainable and continued contributions to the field of entomology and for their greater implications in molecular and cellular biology and the understanding of disease and prevention.” At the time, Leal held 28 Japanese and two U.S. patents.
Said Hammock: “When Walter Leal reached UC Davis, he came with the reputation of being a 'one man army in research.' This reputation was well deserved. I know of no one at UC Davis who matches Walter in taking his remarkable fundamental advances in science and translating them to increase the safety and magnitude of world food production.”
Leal, an expert in insect communication investigates how insects detect odors, connect and communicate within their species; and detect host and non-host plant matter. His research, spanning three decades, targets insects that carry mosquito-borne diseases as well as agricultural pests that damage and destroy crops. He and his lab drew international attention with their discovery of the mode of action of DEET, the gold standard of insect repellents.
He and his collaborators, including Nobel Laureate Kurth Wuthrich (Chemistry 2002), unravel how pheromones are carried by pheromone-binding proteins, precisely delivered to odorant receptors, and finally activated by pheromone-degrading enzymes.
That led to Leal's identification of the sex pheromones of the navel orangeworm (Amyelois transitella), a pest of almonds, figs, pomegranates and walnuts, the major hosts. This has led to practical applications of pest management techniques in the fields.
At the time of his election to NAI Fellow, Joe Rominiecki, communications manager of Entomological Society of America (ESA), said Leal has “greatly advanced scientific understanding of insect olfaction. He has identified and synthesized several insect pheromones, and his collaborative efforts led to the first structure of an insect pheromone-binding protein."
ICE Council. Leal was recently elected chair of the International Congress of Entomology Council, which selects a country to host the congress every four years and which supports the continuity of the international congresses of entomology. Leal succeeds prominent entomologist May Berenbaum of the University of Illinois, Urbana-Champaign, editor-in-chief of the journal, Proceedings of the National Academy of Sciences and a 2014 recipient of the National Medal of Science.
“I have big shoes to fill,” he said.
Ironically, COVID derailed the 2020 NAI ceremony, and Leal--recipient of the Academic Senate's 2022 Distinguished Scholarly Public Service Award for his series of four global webinars educating the public about COVID-19--contracted the disease while in Phoenix for the 2022 ceremony.
“I was treated with Paxlovid, rebounded, and am now fully recovered,” Leal said.
On ESA Honorary Member Ballot. Leal's name is currently on the ESA ballot to become an Honorary Member, the highest ESA honor. The Royal Entomological Society named him an Honorary Fellow in 2015.
A native of Brazil, educated in Brazil and Japan, and fluent in Portuguese, Japanese and English, Leal received his master's degree and doctorate in Japan: his master's degree at Mie University in 1987, and his doctorate in applied biochemistry at Tsukuba University in 1990. Leal then conducted research for 10 years at Japan's National Institute of Sericultural and Entomological Science and the Japan Science and Technology Agency before joining the faculty of the UC Davis Department of Entomology in 2000. He chaired the department from July 2006 to February 2008.
Leal co-chaired the 2016 International Congress of Entomology meeting, "Entomology Without Borders," in Orlando, Fla., that drew the largest delegation of scientists and experts in the history of the discipline: 6682 attendees from 102 countries.
Among his many other honors, Leal is a Fellow of ESA, the American Association for the Advancement of Sciences and the California Academy of Sciences. He is a past president of the International Society of Chemical Ecology and corresponding member of the Brazilian Academy of Sciences. In 2019, ESA selected him to present its annual Founders' Memorial Lecture, the first UC Davis scientist selected to do so.
The hybrid event, organized by the Brazilian Academy of Sciences and CNPq and featuring the keynote lecture and five round tables, is set April 26-27. Registration is underway at https://forms.gle/QKhrbfp7gNuYLUDY8. The seminar, in Portuguese with English translations, will be live on YouTube at https://www.youtube.com/watch?v=ytBA4OA9aOc.
Leal, a corresponding member of the Brazilian Academy of Sciences and a native of Brazil, is a distinguished professor with the Department of Molecular and Cellular Biology, College of Biological Sciences, and former chair of the Department of Entomology, College of Agricultural and Environmental Sciences. In his keynote lecture, Leal will call attention to the CNPq-UC Davis program, “Science without Borders,” which he helped launch 10 years ago to support undergraduate, graduate students and postdoctoral studies at UC Davis.
Leal's hybrid presentation (part recorded and part live) will focus on three “Science Without Border” students whose education at UC Davis played a critical role in launching their careers. One is now an assistant professor at Penn State; another is a data scientist at a Brazilian university; and the third is an entrepreneur. “And one of them met her husband at UC Davis,” Leal related.
- UC Davis Chancellor Gary May will congratulate CNPq in the name of UC Davis, which houses nearly 100 faculty with professional links to Brazil.
- UC Davis distinguished professor Bruce Hammock, the 35-year director of the federally funded UC Davis Superfund Research Program (SRP) (and who holds a joint appointment with the Department of Entomology and Nematology and the Comprehensive Cancer Center), will discuss the history of SRP and his dedication to hosting many Brazilian students, postdocs, and other collaborators.
- UC Irvine distinguished professor Anthony James, professor of microbiology and molecular genetics, who collaborates with UC Davis professor Greg Lanzaro of the School of Veterinary Medicine, will discuss how philanthropy helps to shape current vector biology research.
- World-renowned economist Jose Scheinkman of Brazil, who received an early career scholarship that shaped his career path to the University of Chicago, Princeton, and now Columbia University, will discuss how CNPq plays a key role in the Brazilian scientific economy and its training of scientists.
- John Wingfield, distinguished emeritus professor, UC Davis Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, and former head of the Directorate of Biological Sciences at the National Science Foundation (NSF), will share information on how NSF operates.
Other participants will include Sally Rockey, inaugural executive director of the Foundation for Food and Agriculture Research; Sonny Ramaswamy, former administrator of the National Institute of Food and Agriculture; Professor John Hildebrand, International Secretary of the National Academy of Sciences; Daniel Mucida, head of the Laboratory of Mucosal Immunology at Rockefeller University; Nantel Suzuki, program executive of NASA's Human Landing System; and Scott Hutchins, former Deputy Under Secretary of Agriculture.
Brazilian biomedical scientist Helena Nader will be inaugurated next month as the first female president in the 106-year-history of the Brazilian Academy of Sciences.
Professor Denison, who retired in 2018, joined the department in 1992 and advanced to professor in 1997. He served as a researcher in the UC Davis SRP, funded by National Institute of Environmental Health Sciences (NIEHS), for more than 25 years.
Over a 44-year period, Denison focused his research on understanding the molecular mechanisms by which a protein known as the Ah receptor mediates the biological/toxicological actions of dioxins and related chemicals. He was widely acclaimed for his development of the Chemical Activated LUciferase gene eXpression (CALUX) assay, a cell-based bioassay used to detect specific environmental contaminants, including, but not limited, to dioxin-like chemicals and environmental hormones (endocrine disruptors).
The test, approved by the intergovernmental Organization of Economic Cooperation and the U.S. Department of Environmental Protection Agency, is the international standard for detecting environmental contaminants in the protection of human health. Denison also made other seminal contributions to the Ah receptor field and was a leader in advancing the study of Ah receptor biology, said UC Davis distinguished professor Bruce Hammock, the founding director of UC Davis SRP and a close friend and colleague of Denison's.
“He is best possibly known for his fundamental work on the mechanism of action of TCDD and the translation of this knowledge into a quantitative, rapid and inexpensive assays for tetrachlorodioxin like chemicals and other chemicals that bound to the aryl hydrocarbon hydroxylase receptor," Hammock said. "He went on to use the CALUX format to measure a number of other small molecule receptor interactions. Mike was also funded for much of his career by competitive grants from NIEHS, including his MS and PhD work.”
Robert Rice, professor and chair of the Department of Environmental Toxicology, said that "Mike's absence leaves quite a void in our department. Even in retirement, he continued to be a source of wisdom and amusement, and he was still an inspiration to students."
Rice added that he first met Denison in 1992 when he joined the faculty, "and I ended up being department chair in recent years after he declined the position."
Denison, trained in biology, marine biology, animal physiology and environmental toxicology, received his associate of arts degree in biology from the County College of Morris, N.J. in 1975, and his bachelor's degree in marine biology from St. Francis College, Biddeford, Maine, in 1977. He obtained his master's degree in animal physiology from Mississippi State University, Starkville, in 1980, and went on to receive his doctorate in environmental toxicology from Cornell University, Ithaca, N.Y., in 1983. Denison did postdoctoral research at the Department of Clinical Pharmacology, Hospital for Sick Children, Toronto, Canada, from 1983 to 1985, and with Stanford University's Department of Pharmacology, 1985-1988.
Denison began his academic career as an assistant professor in the Department of Biochemistry at Michigan State University, East Lansing, from 1988 to 1992, and then relocated to the UC Davis Department of Environmental Toxicology.
Michael and his twin brother, Steven, were born on Dec. 8, 1954, in Shirley, Mass., the sons of Alan (deceased) and Alma Denison. While the father served in the U.S. Army, the family lived in numerous places around the world and settled in Wharton, N.J. when boys were 11.
“Michael was a happy and optimistic person,” said his widow Grace Bedoian, who retired in 2014 as a UC Davis SRP administrator and a member of the Hammock lab. “The only thing he took seriously was science, which he loved."
“His typical day was spent at work, conducting his research and mentoring students, returning home and making a wonderful dinner at the end of the day, and then retreating to his home office to work until the wee hours of the following morning," she said. "He maintained curiosity and wonder of the world around him. He loved to solve problems and figure out how things worked. He was generous with his friends and colleagues alike and always quick to offer his services to those in need."
Denison is survived by his widow, Grace; his mother, Alma; two brothers (Steven and Daniel) and their wives (Gloria and Angela); two nieces, two nephews, and several grandnephews.
The family thanks the staff at Yolo Cares of Davis for “their exceptional expertise, kindness and compassion in providing in-home hospice care for Michael. All of the staff members at Yolo Cares are truly angels on this earth.” In lieu of flowers, donations may be made to Yolo Cares by contacting (530) 758-5566 or http://www.yolocares.org.
Donations also may be made to the Michael S. Denison, Ph.D. '83 Environmental Toxicology Research Fund, an endowment created at Cornell University by a colleague. Checks payable to Cornell University may be mailed to Cornell University, Box 37334, Boone, IA 50037-0334. In the memo field or in the correspondence, donors are asked to add: Michael S. Denison, Ph.D. '83 Environmental Toxicology Research Fund #0018594. Online gifts can be made at https://giving.cornell.edu/, notating Michael S. Denison, Ph.D. '83 Environmental Toxicology Research Fund #0018594 on the online giving form. ChristyAgnese, director of development in the College of Agriculture and Life Sciences, Cornell University, may be contacted at (607) 279-6884 for further assistance.
Every year some 10,000 burn victims in the United States undergo an acute inflammatory reaction and die of burn-related infections, according to the Centers for Disease Control and Prevention.
Now a newly published study by a research team from the laboratory of distinguished professor Bruce Hammock, University of California, Davis, and the Department of Surgery, University of Cincinnati College of Medicine (UC CoM), has identified a key regulatory mechanism in inflammation that may lead to new targets for resolving that inflammation—and the inflammation of patients with sepsis, cancer and COVID.
In research published in the current edition of Proceedings of the Natural Academy of Sciences, the scientists announced that they have discovered a pathway that regulates the immune response after infection or injury, such as burns. Dysregulation of this pathway could differentiate those who are at risk of fatal sepsis or help identify targets to resolve this unregulated inflammation.
“We are very excited about the findings in this paper and the far-reaching impacts it could have on understanding a key regulatory step in the immune response,” said co-lead author and researcher Cindy McReynolds of the Hammock lab and director of research at EicOsis, a Davis-based company founded by Hammock. Hammock, the corresponding author of the publication, has been involved in enzyme research for more than 50 years.
“Our previous work identified that these same lipid mediators were up-regulated in severe COVID infections, and we are now finding that these compounds play a role in modulating the immune response so that the body is unable to fight infection or respond properly to trauma without leading to a potentially fatal overreaction,” said McReynolds, who holds a doctorate in pharmacology and toxicology from UC Davis.
“The immunological disbalance we see in many cases of severe burn injury, trauma and sepsis pose a huge clinical challenge as we lack the understanding of how to diagnose and treat it,” said co-lead author Dr. Christian Bergmann, formerly with UC CoM's Department of Surgery and now headquartered in Germany with the University of Ulm's Department of Trauma Surgery, Hand, Plastic and Reconstructive Surgery. “With this work, we reveal an important mechanism how immune cells are functionally disabled by sEH-derived metabolites of linoleic acid.”
“The natural compounds we are studying in this paper are metabolites of linoleic acid (LA), an essential fatty acid the body needs in very small amounts to survive and is only available through the diet,” McReynolds explained. “At lower concentrations, these metabolites are necessary for regulating thermogenesis and heart health but promote inflammation at higher concentrations. LA is more stable and much cheaper than longer chain polyunsaturated fatty acids, so heavily processed foods have higher LA content to increase shelf-life. Additionally, agricultural practices, such as feeding animals corn-based diets, have increased LA in meats and dairy products.”
The research, titled "sEH-Derived Metabolites of Linoleic Acid Drive Pathologic Inflammation while Impairing Key Innate Immune Cell Function in Burn Injury,” is co-authored by Debin Wan, formerly of the Hammock lab and now a scientist at Escape Bio, San Francisco; Nalin Singh of the Hammock lab; and three UC CoM researchers: Charles Caldwell, professor and director, Division of Research, Department of Surgery; Dorothy Supp, adjunct professor in the Department of Surgery and a scientific staff member at Shriners Children's Ohio; and Holly Goetzman, principal research assistant in the Caldwell lab.
“Chronic pain is an enormous emotional and economic burden for more than 100 million people in the United States alone,” said co-author Hammock, who holds a joint appointment with the Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center. "The extreme and poorly treated pain that I observed as a medical officer working in a burn clinic in the Army, is a major driver for me to translate laboratory research to help patients with severe pain and at risk from sepsis." Another major influence: his mother served 15 years as a nurse in a children's hospital burn center, caring for hundreds of patients.
Hammock founded EicOsis in December 2011 to advance novel, safe and effective oral treatments for patients suffering from pain and inflammation. The LLC is developing a new class of oral non-narcotic analgesics based on inhibition of the soluble epoxide hydrolase enzyme. Human clinical trials are underway to test the drug candidate, EC5026, a first-in-class, small molecule that potently inhibits sEH. The sEH inhibitors have already shown to be effective for inflammatory and neuropathic pain in animals, with no apparent adverse or addictive reactions.
Several grants supported the research: Dr. Bergmann received a grant from Deutsche Forschungsgemeinschaft (German Research Foundation) and a National Institutes of Health (NIH) grant from the National Institute of General Medical Sciences (NIGMS); Supp, a grant from the Shriners Hospitals for Children; and Hammock, a RIVER (Revolutionizing Innovative Visionary, Environmental Health) grant from the NIH's National Institute of Environmental Health (NIEHS), and an NIH/NIEHS Superfund Program grant. Hammock has directed the UC Davis Superfund Program for nearly four decades.
“We show that both activities of soluble epoxide hydrolase enzyme (sEH), the center of 50 years work in the Hammock laboratory, and a second integrated phosphatase activity, discovered by us 20 years ago in the same protein, have complementary biological action in vivo, with implications in cardiac biology,” said biochemist and co-author Christophe Morisseau of the Hammock lab who researches the biology and pharmaceutical applications of epoxide hydrolase inhibition in diabetes, pulmonary and cardiovascular diseases.
The research paper, titled “CRISPR/Cas9-mediated Inactivation of the Phosphatase Activity of Soluble Epoxide 1 Hydrolase Prevents Obesity and Cardiac Ischemic Injury,” involved recombinant animal models.
The abstract reads: “Although the physiological role of the C-terminal hydrolase domain of the soluble epoxide hydrolase (sEH-H) is well investigated, the function of its N-terminal phosphatase activity (sEH-P) remains unknown. This study aimed to assess in vivo the physiological role of sEH-P.”
“Such di catalytic activities of separate enzymes jointed during the evolutionary process have been said a Rosetta stone for understanding cell biology,” said co-author Hammock, a UC Davis distinguished professor who holds a joint appointment with the Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center. For the past 50 years, the Hammock lab has been studying sEH inhibitors, leading to drugs that target such diseases as diabetes, hypertension (heart disease), Alzheimer's disease, and cancer. Co-discovered by Hammock and Sarjeet Gill, now a UC Davis distinguished professor at UC Riverside, sEH is a key regulatory enzyme involved in the metabolism of fatty acids.
The work of the UC Davis-French team collaboration may have implications in major diseases of the circulatory system, including atherosclerosis, coronary artery disease, stroke, and hypertension. Research shows that patients with diabetes, obesity, dyslipidemia, cancer, fibrosis, and sepsis have a significant increase in the risk and incidence of cardiovascular disease.
Bellien, a professor in the Department of Pharmacology who holds a doctorate in pharmacology from the Rouen University School of Pharmacy, heads a research group on endothelial protection within INSERM U1096. The endothelium is a thin membrane that lines the inside of the heart and blood vessels. Bellien and his team study the role of endothelial lipid mediators in the pathophysiology of cardiovascular diseases, and notably to study new approaches to treat vascular and valvular calcification. They have been collaborating with the UC Davis team since 2014.