Breaking News
January 22, 2018 - Mallinckrodt Completes Stannsoporfin New Drug Application Filing
January 22, 2018 - ACOG Backs ‘Cascade Testing’ for Cancer-Related Mutations
January 22, 2018 - The terrible toll tennis can take on top players who play too much
January 22, 2018 - KAIST scientists identify cellular mechanism for severe viral hepatitis
January 22, 2018 - New genomic tools provide better understanding of the human immune system
January 22, 2018 - Improving QoL with an App?
January 22, 2018 - First step toward CRISPR cure of Lou Gehrig’s disease
January 22, 2018 - Scientists uncover the proteins responsible for movement
January 22, 2018 - New clinical practice guideline provides recommendations for use of anticoagulants during heart surgery
January 22, 2018 - Depressive symptoms associated with poorer survival in patients with head and neck cancer
January 22, 2018 - Restaurant Bans Have Big Impact on Smoking Rates
January 22, 2018 - D.C. Week: CMS Outlines Path for Medicaid Work Mandate
January 22, 2018 - Study identifies new loci associated with asthma enriched in epigenetic marks
January 22, 2018 - New bug may reduce misery of hay fever sufferers
January 22, 2018 - Specially prepared supplement helps women to run faster, study shows
January 22, 2018 - 3-D Stent Retriever with Aspiration Proves Mettle in AIS
January 22, 2018 - Public health research seeks to understand how natural disasters impact spread of Zika
January 22, 2018 - Research reveals role of nanophenomenon in stimulating bone-repair process
January 22, 2018 - Drinking during late adolescence could be first step to liver problems in adulthood
January 22, 2018 - Epilepsy associated with volume and thickness differences in brain matter
January 22, 2018 - Trevena Announces FDA Acceptance for Review of New Drug Application for Olinvo (oliceridine) Injection
January 22, 2018 - A Noteworthy Margin of Error
January 22, 2018 - Firm advances human trials of revolutionary vaccine
January 22, 2018 - Many Indians put away treating orthopedic problems
January 22, 2018 - Cherwell releases new pocket guide to prepared culture media
January 22, 2018 - Huron earns ISO 13485 certification for quality management system
January 22, 2018 - Avion Pharmaceuticals Announces FDA Approval of Balcoltra (levonorgestrel and ethinyl estradiol tablets and ferrous bisglycinate tablets) Oral Contraceptive
January 22, 2018 - Multi-Gene Test For Early CVD; Neighborhood HF Risk; Novel Testosterone Drugs
January 22, 2018 - Skipping breakfast disrupts ‘clock genes’ that regulate body weight
January 22, 2018 - Creativity May Rely on ‘Teamwork’ in the Brain
January 22, 2018 - NeuroBreak: Alzheimer’s Germ Contest; High Salt Diet May Be Bad for Brain
January 22, 2018 - Diabetics may often fare poorly in hospice care
January 22, 2018 - Performance enhancing benefits of caffeine more apparent for infrequent tea, coffee drinkers
January 22, 2018 - HHS Unveils Framework for Interoperability
January 22, 2018 - More dentists to discuss risks of HPV-related cancers with their patients
January 21, 2018 - Research shows how Zika virus damages placenta to cause malformations in babies
January 21, 2018 - Achaogen Announces FDA Acceptance of New Drug Application with Priority Review for Plazomicin for Treatment of Complicated Urinary Tract Infections and Bloodstream Infections
January 21, 2018 - Drug Allergies: Time to Re-Test?
January 21, 2018 - Mitochondrial protein in cardiac muscle cells linked to heart failure, study finds
January 21, 2018 - Women more likely than men to die from a heart attack
January 21, 2018 - Next generation genomic sequencing can help detect pathogens after joint replacement
January 21, 2018 - Gov’t Shutdown Looms as Senate Debates Spending Bill
January 21, 2018 - Emergency Readiness for Older Adults and People with Disabilities
January 21, 2018 - Heart health at risk for Latinas over worries about deportation
January 21, 2018 - Scientists methodically identify genes related to blood feeding and non-biting mosquitoes
January 21, 2018 - Researchers discover potential target genes to halt thyroid cancer progression
January 21, 2018 - Youth with shared residency after parents’ divorce have less mental issues
January 21, 2018 - Sleep Better, Lose Weight? – Drugs.com MedNews
January 21, 2018 - More $$ Needed for Health Emergencies, Senators Told
January 21, 2018 - Gene test to predict breast cancer recurrence less cost effective in real world practice
January 21, 2018 - Study finds rise in number of adolescents receiving psychiatric or neurodevelopmental diagnosis
January 21, 2018 - Reminders can improve immunization rates
January 21, 2018 - A More Personalized Approach to PSA Screening in 2017
January 21, 2018 - T-cells engineered to outsmart tumors induce clinical responses in relapsed Hodgkin lymphoma
January 21, 2018 - Tetraphase Pharmaceuticals Announces Submission of New Drug Application to FDA for Eravacycline for the Treatment of Complicated Intra-Abdominal Infections (cIAI)
January 21, 2018 - Have Robotics Had a Detrimental Effect on Surgical Residency?
January 21, 2018 - Being bilingual may help autistic children
January 21, 2018 - Metrics Are Not Widespread in Rheumatoid Care
January 21, 2018 - Neuroanatomic abnormalities ID’d in those at risk for autism
January 21, 2018 - Children born with Down’s syndrome have superior genome that compensates for disability
January 21, 2018 - Study finds higher risks for asymptomatic paroxysmal AF patients
January 21, 2018 - The Second Stage of Diet Resolutions
January 21, 2018 - CT Scans Reduce Lung Cancer Deaths … But Among Whom?
January 21, 2018 - ADHD drug use soars among young women
January 21, 2018 - Researchers propose new regulation mechanism linked to action of SirT6 on chromatin
January 21, 2018 - Statins appear to reduce risk of repeated surgery in patients who undergo vitrectomy
January 21, 2018 - Morning Break: Hep A Outbreak Spreads; Tide Pod Challenge; Keeping Lobsters Out of Hot Water
January 21, 2018 - EULAR and ACR present SLE classification criteria at the 2017 ACR/ARHP Annual Meeting
January 21, 2018 - Progenics Pharmaceuticals Announces FDA Acceptance of New Drug Application for Azedra (iobenguane I 131) in Pheochromocytoma and Paraganglioma
January 21, 2018 - House Passes Funding Bill with 6-Year CHIP Renewal
January 21, 2018 - DASH ranked Best Diet Overall for eighth year in a row by U.S. News and World Report
January 21, 2018 - Dementia study sheds light on how damage spreads through brain
January 20, 2018 - Morning Break: Missing Maria Deaths; N.J. Doc Charged in Wife’s Murder; Viva Vaseline!
January 20, 2018 - No interventions proven to prevent late-life dementia
January 20, 2018 - Judge orders new Olympus trial over superbug death
January 20, 2018 - Don’t Rely on Just One Blood Pressure Test for Kids: Study
January 20, 2018 - Going Off the Deep End About Water
January 20, 2018 - Parental attention can reduce risk of drug abuse in adolescence
January 20, 2018 - Mast Uri System offers efficient and cost-friendly diagnostic solution
January 20, 2018 - International SOS, Chatham House sign partnership agreement to further advance Global Health Security Agenda
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