Breaking News
October 20, 2018 - Antidepressant treatment may lead to improvements in sleep quality of patients with depression
October 20, 2018 - Study reports increased risk of death in children with inflammatory bowel disease
October 20, 2018 - Number of Autism Genes Now Tops 100
October 20, 2018 - Total diet replacement programmes are effective for treating obesity
October 20, 2018 - CLARIOstar used for fluorescence measurements on CSIRO’s purpose-built research vessel
October 20, 2018 - People with more copies of AMY1 gene digest starchy carbohydrates faster
October 20, 2018 - Case Comprehensive Cancer Center wins NIH grant to study health disparities
October 20, 2018 - Newly discovered compound shows potential for treating Parkinson’s disease
October 20, 2018 - High rate of non-adherence to hormonal therapy found among premenopausal early breast cancer patients
October 20, 2018 - Immunotherapy medicine found to be effective in treating uveitis
October 20, 2018 - The Pistoia Alliance Calls for Greater Collaboration to Realise Benefits of Innovation and Announces Winners of the 2018 President’s Startup Challenge
October 20, 2018 - Female internists consistently earn less than men
October 20, 2018 - Stanford team looks at dangers of teens’ vaping habits
October 20, 2018 - New approach to understanding cancers will accelerate development of better treatments
October 20, 2018 - LJI and UC San Diego awarded $ 4.5 million as part of NCI’s Cancer Moonshot initiative
October 20, 2018 - School-based HPV vaccination did not increase risky sexual behaviors among adolescent girls
October 20, 2018 - Eye discovery to pave way for more successful corneal transplants
October 20, 2018 - New analysis examines the importance of location in the opioid crisis
October 20, 2018 - Green filters increase reading speed for children with dyslexia
October 19, 2018 - Bariatric Sx Cuts Macrovascular Complications in Obesity, T2DM
October 19, 2018 - Better assessments for early age-related macular degeneration
October 19, 2018 - Visible and valued: Stanford Medicine’s first-ever LGBTQ+ Forum | News Center
October 19, 2018 - Understanding of metal-free enzymes used by bacteria could lead to new effective antibiotics
October 19, 2018 - Beckman Coulter Life Sciences announces new research-focused website
October 19, 2018 - Study finds link between refined soluble fibers, gut microbiota and liver cancer
October 19, 2018 - Social media reduces risk of depression among seniors with pain
October 19, 2018 - Newly developed synthetic DNA molecule may one day be used as ‘vaccine’ for prostate cancer
October 19, 2018 - Preoperative weight loss may not provide health benefits after surgery
October 19, 2018 - U.S. Birth Rates Continue to Drop as Age of New Moms Rises
October 19, 2018 - New technology can keep an eye on babies’ movements in the womb
October 19, 2018 - Juul e-cigarettes pose addiction risk for young users | News Center
October 19, 2018 - Gene sequencing reveals crucial molecular aspects of Trypanosoma brucei
October 19, 2018 - New DNA vaccine strategy protects mice against lethal challenge by multiple H3N2 viruses
October 19, 2018 - Study shows close link between cytokine interleukin-1ß and obesity-promoted colon cancer
October 19, 2018 - Muscle mass plays a critical role in health, shows research
October 19, 2018 - Study finds undiagnosed prediabetes in many infertile men
October 19, 2018 - The Current issue of “The view from here” is concerned with Nanotherapeutic strategies
October 19, 2018 - Delay in replacing the Pap smear with HPV screening is costing lives
October 19, 2018 - Physicians battle pediatric diseases of ear, nose, throat in Zimbabwe | News Center
October 19, 2018 - Researchers investigate why some cancers affect only young women
October 19, 2018 - Drugmakers funnel millions to lawmakers; a few dozen get $100,000-plus
October 19, 2018 - Unselfish people tend to have more children and receive higher salaries
October 19, 2018 - New findings reveal potential cellular players in tumor microenvironment
October 19, 2018 - Some countries take more time for reimbursement decisions on new cancer drugs
October 19, 2018 - Human brain cell transplant offers insights into neurological conditions
October 19, 2018 - Parental education associated with increased family health care spending
October 19, 2018 - New statistical method estimates long- and short-term risk of recurrence of breast cancer in US women
October 19, 2018 - Father’s exposure to nicotine may cause cognitive deficits in descendants
October 19, 2018 - Could we prevent Alzheimer’s disease by treating herpes?
October 19, 2018 - Nurse-led care can be more successful in managing gout
October 19, 2018 - Trump administration, pharma exchange verbal volleys on drug-price transparency
October 19, 2018 - Duke researchers find way to detect blood doping in athletes
October 19, 2018 - Many primary care doctors are still prescribing sedative drugs for older adults
October 19, 2018 - Finger length can predict sexuality in women say researchers
October 19, 2018 - Study finds differences in side-effects experienced by male and female OG cancer patients
October 19, 2018 - Dysfunction of single gene leads to miscarriages
October 19, 2018 - Few Seniors Who Self-Harm Referred for Mental Health Care
October 19, 2018 - Don’t sweat the sweet stuff
October 19, 2018 - URMC researchers discover new approach to deliver therapeutics to the brain
October 19, 2018 - Speech Pathology Australia raises awareness about Developmental Language Disorder
October 19, 2018 - Middlemen suppliers can increase drug prices and hospital bills, say Johns Hopkins researchers
October 19, 2018 - Survey finds high prevalence of HTLV-1 infection among teens and adults in Gabon
October 19, 2018 - Bliss funds research to find whether parental touch can help alleviate pain in premature infants
October 19, 2018 - Human neurons employ highly compartmentalized signaling, study shows
October 19, 2018 - Ultromics expands multiple clinical trials for coronary heart disease to the U.S.
October 19, 2018 - $11 million NIH grant for Clemson University helps launch new center for musculoskeletal research
October 19, 2018 - A new approach identified to control Zika virus, dengue fever
October 19, 2018 - Head Blows Without Concussion May Not Damage Brain, Study Claims
October 19, 2018 - US opioid use not declined, despite focus on abuse and awareness of risk
October 19, 2018 - Next-generation RNA sequencing technology sheds new light on human mitochondrial diseases
October 19, 2018 - UT Southwestern biochemist receives 2019 Breakthrough Prize in Life Sciences for innate immunity discovery
October 19, 2018 - The immune system also plays a key role in day-to-day function of healthy organs
October 19, 2018 - New tool may reveal how the brain structure impacts brain activity, human behavior
October 19, 2018 - Trump Administration announces ‘Winning on Reducing Food Waste’ initiative
October 19, 2018 - For-profit nursing home residents more likely to experience health issues caused by substandard care
October 19, 2018 - Incidence of stroke has risen steadily among marijuana users, show studies
October 19, 2018 - Conceptual framework proposed to examine role of exercise in multiple sclerosis
October 19, 2018 - Near infrared spectroscopy technique for accurate evaluation of chondral injuries
October 19, 2018 - Scientists receive $5.1 million grant to develop stem cell-based therapy for blinding retinal conditions
October 19, 2018 - Shorter physician encounters associated with antibiotic prescribing
Environmental toxin exposure may disrupt function of circadian clock, research shows

Environmental toxin exposure may disrupt function of circadian clock, research shows

image_pdfDownload PDFimage_print

Can environmental toxins disrupt circadian rhythms – the biological “clock” whose disturbance is linked to chronic inflammation and a host of human disorders? Research showing a link between circadian disruption and plankton that have adapted to road salt pollution puts the question squarely on the table.

“This research shows that exposure to environmental toxins may be depressing the function of our circadian clock, the disruption of which is linked to increased rates of cancer, diabetes, obesity, heart disease, and depression,” said Jennifer Hurley, an assistant professor of biological sciences, a member of the Center for Biotechnology and Interdisciplinary Studies (CBIS) at Rensselaer Polytechnic Institute, and senior author on this research. “This is the first time anyone has shown this happening at the level of the core clock, which we had considered to be heavily buffered against these types of environmental effects.”

The research builds on recent findings from the Jefferson Project at Lake George, showing that a common species of zooplankton, Daphnia pulex, can evolve tolerance to moderate levels of road salt in as little as two and a half months. That research produced five populations of Daphnia adapted to salt concentrations ranging from the current concentration of 15 milligrams per liter of chloride in Lake George, to concentrations of 1,000 milligrams per liter as found in highly contaminated lakes in North America.

“Plankton, which are key consumers of algae and a food source for many fish, may be making a monumental tradeoff to tolerate increased road salt,” said Rick Relyea, Jefferson Project director, CBIS member, and co-author of the study. “The circadian rhythm guides these animals through a daily migration, to deep waters during the day to hide from predators and shallow waters at night to feed. Disrupting that rhythm could affect the entire lake ecosystem.”

Hurley said adaptation to salt is likely affecting Daphnia at the epigenetic level, a heritable change in gene levels rather than genetic code. The research has wide applicability in multiple fields beyond human health and is a demonstration of cutting-edge, interdisciplinary research resulting from cross-collaboration between CBIS and the Jefferson Project.

To explore whether salt affects the circadian rhythm of Daphnia, researchers first established that the plankton is governed by a core set of clock-control genes that anticipates the day/night cycle. Clock control genes promote and suppress gene transcription, creating daily oscillations in the levels of enzymes and hormones to affect cell function, division, and growth, as well as physiological parameters such as body temperature and immune responses. The Daphnia genome includes the PERIOD (PER) gene, a set of genes nearly identical to the well-established core clock of the fruit fly (Drosophila melanogaster).

Kayla Coldsnow, a Rensselaer doctoral student and the first author on the study, tracked the expression of the mRNA of PER in Daphnia exposed to naturally low salt levels and constant dark conditions. Despite these constant environmental conditions, Daphnia PER mRNA levels oscillated with a 24-hour rhythm, a clear indication of a functional circadian clock. Her results, in combination with existing research, shows that PER “clock genes” are active in Daphnia.

To test whether adaptation to high-salt environments affects this functional circadian clock, Coldsnow then performed a similar experiment with the five populations of Daphnia produced during her earlier research. Her data showed that PER mRNA rhythms deteriorated with the adaptation to increasing salt concentrations.

“What we see is a graded, measured response in this organism; the higher the level of salt to which the Daphnia are adapted, the more it suppresses the expression of its circadian clock,” said Hurley. “The population adapted to naturally low salt levels exhibits a beautiful, healthy oscillation in PER mRNA expression, but the population adapted to high salt levels have completely lost their ability to oscillate this mRNA expression.”

Hurley said the findings open a new door in circadian research.

“The implications are substantial,” Hurley said. “You’ve exposed Daphnia to an environmental toxin, and its clock was suppressed, probably through epigenetic mechanisms. The clock and biology of Daphnia is very similar to the clock and the biology both in our brains and most organisms. Is it possible that we can see epigenetic changes in the human brain because of exposure to environmental toxins?

“Evolution to environmental contamination ablates the circadian clock of an aquatic sentinel species,” as published in the current edition of Ecology and Evolution, can be found using the DOI: 10.1002/ece3.3490. The research was funded by Rensselaer, The Jefferson Project at Lake George (a partnership of Rensselaer Polytechnic Institute, IBM, and The Fund for Lake George), and a National Science Foundation Graduate Research Fellowship.

Research into circadian rhythms fulfills The New Polytechnic, an emerging paradigm for higher education which recognizes that global challenges and opportunities are so great they cannot be adequately addressed by even the most talented person working alone. Rensselaer serves as a crossroads for collaboration — working with partners across disciplines, sectors, and geographic regions — to address complex global challenges, using the most advanced tools and technologies, many of which are developed at Rensselaer. Research at Rensselaer addresses some of the world’s most pressing technological challenges — from energy security and sustainable development to biotechnology and human health. The New Polytechnic is transformative in the global impact of research, in its innovative pedagogy, and in the lives of students at Rensselaer.

Source:

https://news.rpi.edu/content/2017/11/03/can-environmental-toxins-disrupt-biological-%E2%80%9Cclock%E2%80%9D

Tagged with:

About author

Related Articles