James R. Carey, UC Davis distinguished professor of entomology, will speak Thursday, May 9 at the Walter A. Buehler Alumni Center on “What Can Insect Studies Tell Us about Longevity and Aging? Lots!”
His talk, hosted by the UC Davis Emeriti Association, begins at 11:30. The Alumni Center is located at 530 Alumni Lane. Among the topics he will cover:
- Are there lifespan limits?
- Evolution of lifespan extremes
- Male-female longevity differences
- Evolutionary demography of humans as informed by insect studies
- Three raging controversies in the demography of aging and lifespan in humans
Jeanne Calment of France (1875-1997), who died at age 122 (and 164 days), holds the record of the longest confirmed human lifespan.
An internationally recognized leader and distinguished scholar in insect demography and invasion biology, spanning three decades, Carey also researches health demography, biology of aging, and lifespan theory. He is the author of a landmark study published in the journal Science in 1992 that showed mortality of Mediterranean fruit flies (medflies) slows at older ages. Scientists last year confirmed that this also occurs in humans, citing the study of 105-year-old Italian women.
Carey, who joined the UC Davis Department of Entomology (now Entomology and Nematology) in 1980, directed an 11-university, $10 million, 10-year study on biodemography of aging from 2003-2013. He is also known for discovering Carey's Equality or the death distribution in a life table population equals its age structure. He teaches a popular longevity course that draws 250 to 300 students year, and recently authored a book on biodemography, to be published by Princeton University next year.
Carey drew a large crowd for his Science Café presentation Oct.10 on "Are There Upper Limits to Human Lifespan?” in the G St. Wunderbar, Davis.
The talk is open to the public. Those who want to have lunch must make reservations by Monday, May 6 to the UC Davis Emeriti Association at (530) 752-5182 or email@example.com.
She and colleague Rebecca Rensberg sequenced the genes that encode for the spider glue protein. Their work appears in the April edition of the journal G3-Genes Genomes Genetics.
Stellwagen said she is particularly interested in the "biomechanical properties and genetics of silk, particularly the aggregate glue that orb-weaving spiders deposit on the capture spiral silk of their webs."
"I'll be talking about the biomechanics of spider glue--how droplets of glue on a spiders web stretch, and how environmental variables like humidity, temperature, and ultraviolet light affect that stretch," Stellwagen said. "I'll also be talking about the molecular biology of the glue--discovering the DNA sequences that code for main proteins that make up the glue, and how that sequence relates to the mechanical properties."
Stellwagen said that "most people are unaware of the glue on a spider's web because you can't see the droplets with your naked eye, but it's a really important feature of the web that spiders rely on to capture prey. Spider glue is also a modified silk protein, but has lost its fibrous characteristics that we think of when we hear the word silk. Currently, there are only around 20 full-length silk genes known--but many, many partial sequences--because these genes are really hard to sequence due to their size and repetitiveness. I'll talk about why it's so difficult to sequence silk genes, and what got my research over the hurdles."
An individual orb weaving spider can spin up to seven different types of silk, cach with unique functions and material properties, Stellwagen explained. "The capture spiral silk of classic two-dimensional aéenal orb webs is coated with amorphous glue droplets that function to retain prey that get caught in a web. The glue differs from solid silk fibers as it is a viscoelastic, amorphic, wet material that is responsive to environmental conditions. Humidity causes changes in the glue's maternal properties, like stretchiness and adhesion, while temperature mediates these affects. The glue is more or less resistant to damage caused by ultraviolet radiation depending on a species' habitat."
"At the molecular level, spider glue is a modified silk that is mostly comprised of proteins called spidroins (spider fibroins) encoded by two members of the silk gene family."
Stellwagen, whose postdoctoral research focuses on arachnids, is currently working with Mercedes Burns studying population genetics of Japanese facultative parthenogenic harvestmen. Using Oxford Nanopore, she is sequencing the genome of the polyploid species Leiobunum manubriatum in an effort to understand their mixed ploidy and sexual/asexual reproductive modes.
Stellwagen received her doctorate in biological sciences in July of 2015 from Virginia Polytechnic Institute and State University, Blacksburg, Va. Her dissertation: "Structure and Function of the Viscous Capture Spiral and its Relationship to the Architecture of Spider Orb Webs." She holds two degrees from Clemson University, South Carolina: a bachelor's degree and a master's degree. Her master's thesis: "Spider (Aranea) Diversity, Habitat Distributions and Pitfall Trapping in Kings Mountain National Military Park, South Carolina."
Stellwagen has also published her work on spider glue in the Journal of Experimental Biology and the Journal of Arachnology. She delivered oral presentations on "Towards Spider Glue: Sequencing the Longest Known Silk Family Gene" at the 2019 International Congress of of Arachnology, Christchurch, New Zealand, and the 2018 American Arachnological Society Annual Meeting in Ypsilanti, Mich.
Seminar hosts are Hanna Kahl, UC Davis doctoral student in entomology, and Jason Bond, the Evert and Marion Schlinger Endowed Chair in Insect Systematics, UC Davis Department of Entomology and Nematology.
The seminars, coordinated by medical entomologist/assistant professor Geoffrey Attardo, take place at 4:10 p.m. every Wednesday in Room 122 of Briggs Hall, through June 5. (See list of seminars)
Sarah Stellwagen's website
Hölldobler, an evolutionary biologist based at Arizona State University researches the evolution and social organization in ants. He says that colonies that are "true superorganisms, show great cooperation among their nest mates and exhibit fierce aggression against neighboring conspecific colonies and display complex territorial strategies." His experimental and theoretical contributions cover sociobiology, behavioral ecology, and chemical ecology.
Hölldobler and co-author E. O. Wilson won the Pulitzer Prize for non-fiction writing in 1990 for their book, The Ants. They also co-authored The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies and Journey to the Ants: A Journey of Scientific Exploration. Hölldobler is also the author of The Leafcutter Ants.
A native of Bavaria, Germany (born June 25, 1936), he studied biology and chemistry at the University of Würzburg. He wrote his doctoral thesis on the social behavior of the male carpenter ant and their role in the organization of carpenter ant societies.
Hölldobler began his academic career at the University of Frankfurt in 1971 as a professor of zoology. From 1973 to 1990 he served as professor of biology and the Alexander Agassiz professor of zoology at Harvard University, Cambridge, Mass. Hölldobler returned to Germany in 1989 to accept the chair of behavioral physiology and sociobiology at the Theodor-Boveri-Institute of the University of Würzburg.
From 2002 to 2008, Hölldobler was an Andrew D. White Professor-at-Large at Cornell University, Ithaca, N.Y. Since his retirement in 2004, he has worked at Arizona State University (ASU) as a professor and research scientist. A Regents' and Foundation professor, he is one of the founders of the Social Insect Research Group (SIRG) and of the Center for Social Dynamics and Complexity.
The seminars are coordinated by medical entomologist/assistant professor Geoffrey Attardo and take place at 4:10 p.m. every Wednesday through June 5 in 122 Briggs Hall. (See list of seminars)/span>
Picnic Day serves as the university's annual open house for prospective and current students, families, alumni, staff, faculty, and the greater Davis and regional communities. It all begins with the parade opening ceremony at 9:30 a.m. by the grandstands on North Quad Avenue, across from Wickson Hall. The parade begins at 10 a.m. Most Picnic Day events will run from 10 a.m. to 4 or 4 p.m. (See more information on the campus website.)
At Briggs Hall, home of the UC Davis Department of Entomology and Nematology, activities will take place from 9 a.m. to around 4:30 p.m., while the Bohart Museum will be open from 11 a.m. to 2 p.m.--shorter hours to enable the Bohart scientists and volunteers to help at Briggs Hall and with the UC Davis Picnic Day Parade. The UC Davis Entomology Club's parade entry is a gigantic black widow spider.
The Bohart Museum, themed, "Will Travel for Bugs: The Bohart Museum of Entomology's Collections from Around the World," is nominated for a people's choice award, as is the honey tasting at Briggs Hall. QR codes will be at each site. "Visitors will have the opportunity to vote for their favorite exhibits in five award categories," according to Madhuri Narayan, UC Davis Picnic Day exhibits director. Folks can vote by QR or vote here from 8 a.m. to 10 p.m. April 13. The prize for earning the most votes? "An awesome certificate and bragging rights," Narayan said.
Briggs Hall. Among the scheduled events:
- Cockroach Races: Participants can pick their favorite "roach athlete" and cheer it to victory.
- Honey Tasting: Extension apiculturist Elina Lastro Niño is planning on a number of varietals of honey.
- Maggot Art: Participants will dip a maggot into water-based, non-toxic paint and position it on paper and let it crawl. Voila! Maggot art, suitable for framing.
- Virtual Reality Bugs: Medical entomologist Geoffrey Attardo will set up a virtual reality system to enable people to view three dimensional models of insects. In VR, the models can be made to look life size, 40 feet tall or anywhere in between, he says. Here's the link that to view them in your web browser: https://skfb.ly/6xVru
- Bee Observation Hive: Viewers can check out the queen, workers and drones in the bee observation hive and see tools used in beekeeping.
- Bug Doctor: The Doctor Is In: Graduate students will identify insects and arachnids and answer questions
- IPM Booth: UC Statewide Integrated Pest Management Program professionals will discuss and answer questions about insect pests, beneficial insects and pest control. They will display their publications and live insects. In keeping with tradition, they will give away free lady beetles (lady bugs), to be released in gardens to devour aphids and other soft-bodied insects.
- Ants: Graduate students from Professor Phil Ward's lab will talk to visitors about the amazing world of ants.
- Mosquito Abatement: Sacramento-Yolo Mosquito and Vector Control District professionals will staff a booth
- Dr. Death: Forensic entomologist Robert Kimsey will staff his traditional Dr. Death booth, inviting the visitors to ask questions and look through microscopes.
- Davis Fly Fishers: The anglers will demonstrate fly-tying techniques in Briggs 158
- Aquatic Insects: Professor Sharon Lawler's lab will display a number of aquatic insects.
- Scavenger Hunt: Participants will search for and identify insects.
- Insect Face Painting: Entomology Club members will face-paint bees, butterflies, lady beetles and other insects
- T-Shirt Sales: Visitors can take their pick or picks among insect-themed t-shirts (popular t-shirts include beetles and honey bees). Newly printed t-shirts feature the roach races, an American Gothic of entomologists, and a cicada plugged into an amp. Selection and prices are online at https://mkt.com/UCDavisEntGrad/
- Bake Sale: The Entomology Club will offer insect-themed baked goods.
"At the Bohart, we are focusing on the various countries from around the world and some of their insect fauna," said Tabatha Yang, education and outreach coordinator. The 12 countries that the Bohart is highlighting, besides the United States, are Australia, Belize, Democratic Republic of Congo, Korea, Madagascar, Malayasia, Mexico,Papua New Guinea, Peru, Republic of South Africa, and Turkey.
“So for anyone who is from there, has lived there, has visited there, or who wants to visit there, please come and take a peak at some unique insects from around the world,” Yang said. “Some people enjoy traveling to explore cuisine and culture, but traveling for the flora and fauna of the world is equally wonderful. Insects are an important part of nature, so be curious, not afraid.”
The Bohart Museum was founded in 1946 by UC Davis entomologist Richard “Doc” Bohart (1913-2007). It is the home of nearly eight million insect specimens, plus a year-around gift shop and a live "petting zoo" that includes Madagascar hissing cockroaches, stick insects, tarantulas and praying mantids. The gift shop is stocked with books, jewlery, t-shirts, insect-collecting equipment, insect-themed candy, and stuffed animals.
The Bohart Museum is open to the general public Mondays through Thursdays, from 9 a.m. to noon and from 1 to 5 p.m., plus occasional, weekend open houses. Admission is free. Further information is available on the Bohart Museum website.
The UC Davis Department of Entomology and Nematology is chaired by nematologist/professor Steve Nadler. Molecular geneticist/physiologist Joanna Chiu, associate professor, serves as the vice chair.
An enzyme inhibitor developed in the UC Davis laboratory of Bruce Hammock and tested in mice by a team of international researchers shows promise that it could lead to a drug to prevent or reduce the disabilities associated with the neurodevelopmental disorders of autism and schizophrenia.
“We discovered that soluble epoxide hydrolase (sEH) plays a key role in inflammation associated with neurodevelopmental disorders. Inhibiting that enzyme stops the inflammation and the development of autism-like and schizophrenia-like symptoms in animal models,” said collaborator Kenji Hashimoto, a professor with the Chiba University Center for Forensic Mental Health, Japan. The scientists found higher levels of sEH in a key region of the brain—the prefrontal cortex of juvenile offspring-- after maternal immune activation (MIA).
“Mothers who have MIA, which results from severe stress in that region of the brain, have an increased occurrence of neurodevelopment disorders in their offspring,” Hashimoto explained. “In our study, the sEH enzyme increased dramatically in a key brain region of mice pups from mothers with MIA.”
The research, published today (March 18) in the Proceedings of the National Academy of Sciences (PNAS), is the work of 14 researchers from Chiba University Center for Forensic Mental Health; the Laboratory for Molecular Psychiatry, RIKEN Center for Brain Science, in Wako, Saitama, Japan; and the Hammock laboratory.
Research in Mice Pups
By inhibiting sEH, the researchers reversed cognitive and social interaction deficiencies in the mice pups. They hypothesize that this is due to increasing natural chemicals, which prevent brain inflammation. In people, this could reduce the disabilities associated with autism, such as anxiety, gastrointestinal disturbances and epilepsy.
“The same chemical and biochemical markers behaved as predicted in human stem cells,” said Hammock, a distinguished professor who holds a joint appointment with the Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center.
Earlier studies have indicated a genetic disposition to the disorders. The team also studied postmortem brain samples from autism patients that confirmed the alterations.
“In the case of both autism and schizophrenia, the epidemiology suggests that both genetics and environment are contributing factors,” said neuroscientist and associate professor Amy Ramsey of the Department of Pharmacology and Toxicology, University of Toronto, who was not involved in the study. “In both cases, maternal infection is a risk factor that might tip the scales for a fetus with a genetic vulnerability. This study is important because it shows that their drug can effectively prevent some of the negative outcomes that occur with prenatal infections. While there are many studies that must be done to ensure its safe use in pregnant women, it could mitigate the neurological impacts of infection during pregnancy.”
Neuroscientist Lawrence David, professor and chair of the School of Public Health, University of Albany, N.Y., who was not involved in the research, said that the study might lead to “an important therapeutic intervention for neurodevelopment disorders.”
Might Be Important Therapeutic Invervention
“There is increasing evidence that maternal immune activation activities (MIA) during fetal development can lead to aberrant neurobehaviors, including autistic-like activities,” said Lawrence, who studies neuroimmunology and immunotoxicology. The study “suggests that enzymatic control of fatty acid metabolism is implicated in neuroinflammation associated with schizophrenia and autism spectrum disorders. The expression of Ephx2 giving rise to soluble epoxide hydrolase (sEH) influences production of fatty acid metabolites, which elevate inflammation in the experimental model of mice after MIA; the sEH inhibitor TPPU (N-[1-(1-oxopropyl)-4-piperidinyl]-N'-[4-(trifluoromethoxy)phenyl)-urea) was postnatally used to improved behaviors. Analysis of cadaver brains from individuals with ASD also expressed increased sEH. Fatty acid metabolites have been known to affect fetal development, especially that of the brain; therefore, TPPU might be an important therapeutic intervention for neurodevelopmental disorders.”
Molecular bioscientist Isaac Pessah of the UC Davis School of Veterinary Medicine, distinguished professor and associate dean of research and graduate education in the Department of Molecular Biosciences, described the findings as “significant” and called for more detailed and expanded studies.
“There is mounting evidence that inappropriate maternal immune responses during pregnancy to infection contributes elevated risk to autism spectrum disorder, at least in a fraction of cases,” Pessah said. “The most significant findings reported here is that a commonly used mouse model of immune-triggered behavioral deficits mimicking some of the core symptoms in autistic children can be suppressed by inhibiting a novel biochemical target, soluble epoxide hydrolase; a target not previously explored as a target for therapeutic intervention to treat ASDs. These findings provide a rational basis for more detailed and expanded studies in mice carrying mutations implicated in ASDs to determine whether the therapeutic benefits of soluble epoxide hydrolase inhibitor(s) observed in this study are more generalizable.”
Autism in the United States
The Center for Disease Control and Prevention (CDC) estimates that 1 in 68 children in the United States have autism, commonly diagnosed around age 3. It is four times more common in boys than girls. CDC defines autism spectrum disorder as a “developmental disability that can cause significant social, communication and behavioral challenges.” The disorder impairs the ability to communicate and interact.
Approximately 3.5 million people or 1.2 percent of the population in the United States are diagnosed with schizophrenia, one of the leading causes of disability, according to the Schizophrenia and Related Disorders Alliance of America (SARDAA). Scores more go unreported. Approximately three-quarters of persons with schizophrenia develop the illness between 16 and 25 years of age. Statistics also show that between one-third and one half of all homeless adults have schizophrenia, and 50 percent of people diagnosed have received no treatment. Among the symptoms: delusions, hallucinations, disorganized speech, disorganized or catatonic behavior, and obsessive-compulsive disorders, such as hoarding, according to SARDAA.
Promising Prophylactic or Theraputic Target
In their research paper, titled “Key Role of Soluble Epoxide Hydrolase in the Neurodevelopmental Disorders of Offspring After Maternal Immune Activation,” the scientists described sEH as “a promising prophylactic or therapeutic target for neurodevelopmental disorders in offspring after MIA.”
First author Min Ma and second Qian Ren of the Hashimoto lab conducted the animal and biochemical work, while chemists Jun Yang and Sung Hee Hwang of the Hammock lab performed the chemistry and analytical chemistry. Takeo Yoshikawa, a team leader with the RIKEN's Molecular Psychiatry Laboratory, performed measurements of gene expression in the neurospheres from iPSC (induced pluripotent stem cells) from schizophrenia patients and postmortem brain samples from autism patients.
Hashimoto described the international collaboration as “exciting and productive.” This is their third PNAS paper in a series leading to endoplasmic reticulum stress. “We report discovery of a biochemical axis that leads to multiple neurological disorders, including depression, Parkinson's disease, schizophrenia, autism spectrum disorders and similar diseases,” he said.
First Human Trials
William Schmidt, vice president of clinical development at EicOsis, a Davis-based company developing inhibitors to sEH to treat unmet medical needs in humans and companion animals, said the company is developing a first-in-class therapy for neuropathic and inflammatory pain. “EicOsis is in the process of finalizing our first human trials on the inhibitors of the soluble epoxide hydrolase, originally reported from UC Davis,” Schmidt said. “We are targeting the compounds as opioid replacements to treat peripheral neuropathic pain. It is exciting that the same compound series may be used to prevent or treat diseases of the central nervous system.”
Several grants from the National Institutes of Health, awarded to Hammock, supported the research. Hammock praised the many collaborators and students he has worked with on the project. “This work illustrates the value of research universities in bringing together the diverse talent needed to address complex problems,” Hammock said. “It also illustrates the value of fundamental science. This autism research can be traced directly to the fundamental question of how caterpillars turn into butterflies.”
Now working solely on research to benefit humankind, Hammock began his career in insect science at UC Berkeley where he investigated how epoxide hydrolase degrades a caterpillar's juvenile hormone. The process leads to metamorphosis from the larval stage to the adult insect. Hammock then wondered "Does the enzyme occur in plants? Does it occur in mammals?"
It does, and particularly as a soluble epoxide hydrolase in mammals.
"Science is full of surprises," said Hammock, who founded EicOsis to help human patients conquer pain without opioids. "We need to remember that the concept, the clinical target, and even the chemical structure, came from asking how caterpillars turn into butterflies."
ABSTRACT, PNAS Paper, "Key Role of Soluble Epoxide Hydrolase in the Neurodevelopmental Disorders of Offspring After Maternal Immune Activation"
“Maternal infection during pregnancy increases the risk of neurodevelopmental disorders such as schizophrenia and autism spectrum disorder (ASD) in offspring. In rodents, maternal immune activation (MIA) yields offspring with schizophrenia- and ASD-like behavioral abnormalities. Soluble epoxide hydrolase (sEH) plays a key role in inflammation associated with neurodevelopmental disorders. Here we found higher levels of sEH in the prefrontal cortex (PFC) of juvenile offspring after MIA. Oxylipin analysis showed decreased levels of epoxy-fatty acids in the PFC of juvenile offspring after MIA, supporting increased activity of sEH in the PFC of juvenile offspring. Furthermore, the expression of sEH (or EPHX2) mRNA in iPSC-derived neurospheres from schizophrenia patients with the 22q11.2 deletion was higher than that of healthy controls. Moreover, the expression of EPHX2 mRNA in the postmortem brain samples (Brodmann area 9 and 40) from ASD patients was higher than that of controls. Treatment of TPPU (a potent sEH inhibitor) into juvenile offspring from P28 to P56 could prevent cognitive deficits and loss of parvalbumin (PV)-immunoreactivity in the medial PFC of adult offspring after MIA. In addition, dosing of TPPU to pregnant mothers from E5 to P21 could prevent cognitive deficits, and social interaction deficits and PV-immunoreactivity in the mPFC of juvenile offspring after MIA. These findings suggest that increased activity of sEH in the PFC plays a key role in the etiology of neurodevelopmental disorders in offspring after MIA. Therefore, sEH would represent a promising prophylactic or therapeutic target for neurodevelopmental disorders in offspring after MIA.”
Related Research Published in PNAS
- Soluble Epoxide Hydrolase Plays a Key Role in the Pathogenesis of Parkinson's Disease
- Gene Deficiency and Pharmacological Inhibition of Soluble Epoxide Hydrolase Confers Resilience to Repeated Social Defeat Stress