Health impact of chemicals in plastics is handed down two generations

UC Riverside mouse study finds paternal exposure to phthalates increases risk of metabolic diseases in progeny
Photo Credit: Meruyert Gonullu

Fathers exposed to chemicals in plastics can affect the metabolic health of their offspring for two generations, a University of California, Riverside, mouse study reports.

Plastics, which are now ubiquitous, contain endocrine disrupting chemicals, or EDCs, that have been linked to increased risk of many chronic diseases; parental exposure to EDCs, for example, has been shown to cause metabolic disorders, including obesity and diabetes, in the offspring.

Most studies have focused on the impact of maternal EDC exposure on the offspring’s health. The current study, published in the journal Environmental International, focused on the effects of paternal EDC exposure.

Led by Changcheng Zhou, a professor of biomedical sciences in the School of Medicine, the researchers investigated the impact of paternal exposure to a phthalate called dicyclohexyl phthalate, or DCHP, on the metabolic health of first generation (F1) and second generation (F2) offspring in mice. Phthalates are chemicals used to make plastics more durable.

Astronomers use novel technique to find starspots

Sunspots
Image Credit: HMI / SFLORG/ Via ESO Helioviewer

Astronomers have developed a powerful technique for identifying starspots, according to research presented this month at the 241st meeting of the American Astronomical Society, and published in the journal Monthly Notices of the Royal Astronomical Society

Our sun is at times dotted with sunspots, cool dark regions on the stellar surface generated by strong magnetic fields, which suppress churning motions and impede the free escape of light. "On other stars, these phenomena are called starspots," said Lyra Cao, lead author of the study and a graduate student in astronomy at The Ohio State University. 

“Our study is the first to precisely characterize the spottiness of stars and use it to directly test theories of stellar magnetism,” said Cao. “This technique is so precise and broadly applicable that it can become a powerful new tool in the study of stellar physics.”

Use of the technique will soon allow Cao and her colleagues to release a catalog of starspot and magnetic field measurements for more than 700,000 stars – increasing the number of these measurements available to scientists by three orders of magnitude.

Researchers Unveil New Collection of Human Brain Atlases that Chart Postnatal Development

Surface-volume atlases from 2 weeks to 24 months.
Image Credit: © 2023, Ahmad et al., CCBY 4.0

Led by Pew-Thian Yap, PhD, researchers at the UNC School of Medicine created monthly infant brain atlases to help researchers analyze the developing brain in detail to investigate neurological disorders and other conditions.

Human brain atlases can be used by medical professionals to track normative trends over time and to pinpoint crucial aspects of early brain development. By using these atlases, they are able to see what typical structural and functional development looks like, making it easier for them to spot the symptoms of abnormal development, such as attention-deficit / hyperactivity disorder (ADHD), dyslexia, and cerebral palsy.

Pew-Thian Yap, PhD, professor in the UNC Department of Radiology, and colleagues in the department and the Biomedical Research Imaging Center (BRIC) have created a new collection of month-by-month infant brain atlas (IBA) that capture fine spatiotemporal details of the early developing brain.

Supplementation with amino acid serine eases neuropathy in diabetic mice

From left: Michal Handzlik and Christian Metallo
Photo Credit: Salk Institute

Approximately half of people with type 1 or type 2 diabetes experience peripheral neuropathy—weakness, numbness, and pain, primarily in the hands and feet. The condition occurs when high levels of sugar circulating in the blood damage peripheral nerves. Now, working with mice, Salk Institute researchers, in collaboration with the University of California San Diego, have identified another factor contributing to diabetes-associated peripheral neuropathy: altered amino acid metabolism.

The study, published in Nature, adds to growing evidence that some often-underappreciated, “non-essential” amino acids play important roles in the nervous system. The findings may provide a new way to identify people at high risk for peripheral neuropathy, as well as a potential treatment option. The team included UC San Diego bioengineering professor Prashant Mali, microbiome expert professor Rob Knight and pathologist Nigel A. Calcutt.

“We were surprised that dialing up and down a non-essential amino acid had such a profound effect on metabolism and diabetic complications,” says senior author Christian Metallo, a professor in Salk’s Molecular and Cell Biology Laboratory. “It just goes to show that what we think of as dogma can change under different circumstances, such as in disease conditions.”

Evolutionary Tuning of a Cellular “Powerhouse”

Profiles of the subunits of individual complexes (top) and overall representation of all around 5200 protein signals in MitCOM.
Image Source | Credit: AG Fackler/Pfanner/Becker

Mitochondria are membrane-enclosed structures found in all cells of higher organisms, where they produce most of the necessary energy (“powerhouses of the cell”). In addition, these organelles serve important functions in the synthesis and degradation of certain biomolecules as well as in numerous intercellular signaling processes. In close collaboration, a team of researchers led by Prof. Dr. Nikolaus Pfanner and Prof. Dr. Bernd Fakler from the University of Freiburg Institutes of Biochemistry and Physiology, respectively, and by Prof. Dr. Thomas Becker from the Institute of Biochemistry at the University of Bonn has now applied a newly developed analytical method to comprehensively map the structural organization of proteins in mitochondria. The results provide initial insight into the structure and organization of the mitochondrial proteins in protein machineries of varying complexity, thus laying the foundation for future studies of new protein functions and structures. This study was published in the journal Nature.

Comprehensive picture of the composition of protein complexes indispensable

Mechanical forces in the nervous system play a corrective role

The researchers visualized the forces acting on dendrites during pruning by measuring their lengths (blue/red) and the angles at dendritic branchpoints: A) before, B) after dendrite severing,
Image Credit: WWU - Rumpf Lab

Researchers at Münster University show in the fruit fly how mechanical tearing cuts neural connections

Nerve cells communicate with one another via long processes known as axons and dendrites, or, more generally, neurites. During development, these processes first grow and form connections with other cells, for example synapses with other nerve cells. Any neurites which are not properly linked, or are no longer needed, are removed by a corrective mechanism known as “pruning”. Such pruning processes can appear drastic, and neurites sometimes seem to be severed directly from the nerve cell. Researchers headed by Dr. Sebastian Rumpf from the Institute of Neuro- and Behavioral Biology at Münster University has now found the mechanism of neurite severing. In a study published in the Journal of Cell Biology, the team show that in sensory nerve cells of the fruit fly Drosophila melanogaster, pruning occurs through mechanical tearing.

Mercury Helps to Detail Earth’s Most Massive Extinction Event

The Karoo Basin in South Africa yields clues about the largest mass extinction in earth's history
Photo Credit: Juanita Swart

The Latest Permian Mass Extinction (LPME) was the largest extinction in Earth’s history to date, killing between 80-90% of life on the planet, though finding definitive evidence for what caused the dramatic changes in climate has eluded experts.

An international team of scientists, including UConn Department of Earth Sciences researchers Professor and Department Head Tracy Frank and Professor Christopher Fielding, are working to understand the cause and how the events of the LPME unfolded by focusing on mercury from Siberian volcanoes that ended up in sediments in Australia and South Africa. The research has been published in Nature Communications.

Though the LPME happened over 250 million years ago, there are similarities to the major climate changes happening today, explains Frank:

“It’s relevant to understanding what might happen on earth in the future. The main cause of climate change is related to a massive injection of carbon dioxide into the atmosphere around the time of the extinction, which led to rapid warming.”

Power of cancer drugs may see boost by targeting newly identified pathway

Proteins labeled with colored tags fill the main compartment — but not the nuclei (blue) — of human cervical cancer cells. Green cells contain the protein TRPV2, red cells contain STING, and yellow and orange cells contain a mixture of both. The proteins are part of a newly discovered DNA-protection pathway that potentially could be targeted to improve cancer therapies, according to researchers at Washington University School of Medicine in St. Louis.
Image Credit: Lingzhen Kong

Cells zealously protect the integrity of their genomes, because damage can lead to cancer or cell death. The genome — a cell’s complete set of DNA — is most vulnerable while it is being duplicated before a cell divides. Cancer cells constantly are dividing, so their genomes are constantly in jeopardy.

Researchers at Washington University School of Medicine in St. Louis has identified a previously unknown signaling pathway cells use to protect their DNA while it is being copied. The findings, published in the journal Molecular Cell, suggest that targeting this pathway potentially could boost the potency of cancer therapeutics.

“A cell that can’t protect its genome is going to die,” said senior author Zhongsheng You, a professor of cell biology and physiology. “This entire pathway we found exists to protect the genome so the cell can survive in the face of replication stress. By combining inhibitors of this pathway with chemotherapy drugs that target the DNA replication process, we potentially could make such drugs more effective.”

Pioneering approach advances study of CTCF protein in transcription biology

Scientists at St. Jude collaborated to better understand CTCF. L to R: Beisi Xu, PhD, Chunliang Li, PhD; Judith Hyle; Mohamed Nadhir Djekidel, PhD.
Photo Credit: St. Jude Children's Research Hospital

Scientists at St. Jude Children’s Research Hospital used the auxin-inducible degron 2 system on CTCF, bringing the novel approach to bear on a fundamental protein.

CTCF is a critical protein known to play various roles in key biological processes such as transcription. Scientists at St. Jude Children’s Research Hospital used a next-generation protein degradation technology to study CTCF. Their work revealed the superiority of the approach in addition to providing functional insights into how CTCF regulates transcription. The study, published today in Genome Biology, paves the way for more clear, nuanced studies of CTCF.

Transcription is an essential biological process where DNA is copied into RNA. The process is the first required step in a cell to take the instructions housed in DNA and ultimately translate that code into the amino acid or polypeptide building blocks that become active proteins. Dysregulated transcription plays a role in many types of pediatric cancer. Finding ways to modify or target aspects of the transcriptional machinery is a novel frontier in the search for vulnerabilities that can be exploited therapeutically.

While the biology of CTCF has been extensively studied, how the different domains (parts) of CTCF function in relation to transcription regulation remains unclear.

Fossils of Arctic primate relatives tell climate-adaptation story

Artist's reconstruction of Ignacius dawsonae surviving six months of winter darkness in the extinct warm temperate ecosystem of Ellesmere Island, Arctic Canada.
Illustration Credit: Kristen Miller, Biodiversity Institute, University of Kansas.

Two sister species of near-primate, called “primatomorphans,” dating back about 52 million years have been identified by researchers at the University of Kansas as the oldest to have dwelled north of the Arctic Circle. The findings was published in the peer-reviewed journal PLOS ONE.

According to lead author Kristen Miller, doctoral student with KU’s Biodiversity Institute and Natural History Museum, both species — Ignacius mckennai and I. dawsonae — descended from a common northbound ancestor who possessed a spirit “to boldly go where no primate has gone before.”

The specimens were discovered on Ellesmere Island, Nunavut, Canada, in layers of sediment linked with the early Eocene, an epoch of warmer temperatures that could foretell how ecosystems will fare in coming years due to human-driven climate change.

“No primate relative has ever been found at such extreme latitudes,” Miller said. “They’re more usually found around the equator in tropical regions. I was able to do a phylogenetic analysis, which helped me understand how the fossils from Ellesmere Island are related to species found in midlatitudes of North America — places like New Mexico, Colorado, Wyoming and Montana. Even down in Texas we have some fossils that belong to this family as well.”