Category Archives: Physiology

Physiology

World Space Week was held from 4 to 10 October – India Education Diary

PetrSU scientists are summing up the results of their scientific research in the field of space physiology.Since 2015, the Department of Human and Animal Physiology, Pathophysiology, Histology of the Medical Institute of PetrSU has been conducting research to study the effect of ground-based simulated weightlessness on the body of an elderly person suffering from Parkinsons disease.

This year there were 3 articles in the journal Human Physiology and 2 articles in the journal Frontiers in Physiology, 3 articles are under review or ready for submission.

It should be said that, judging by the statistics of readings and downloads, the interest in these articles is huge, especially in Germany, Belgium, the USA and the PRC. We attribute this to recent flights to suborbital space by two private spaceships Jeff Bazos on Blue Origin and Richard Branson on VVS Unit with a crew of elderly tourists.

As a prospect, we reported in our articles that soon flights of older people into suborbital space will be a reality, but there is little research on the physiology of an elderly person in space, and on a person with neurodegenerative diseases, there are no at all. Our studies have shown that a short-term state of weightlessness, with careful selection of applicants, does not have negative consequences for the cardiovascular system, even for a patient with parkinsonism. In some respects, this flight is even useful. In fact, with our work, we have closed a large gap in space physiology and the rationale for space tourism. The recent arrival on the ISS of a team to shoot the first space movie only confirms this trend.

said medical scientists, professors A.Yu. Meigal and L.I. Gerasimova-Meigal.

In April of this year, the Human in Space conference was held, in May the traditional conference of the International Society of Gravitational Physiology (ISGP42), which were dedicated to the 60th anniversary of the first manned flight into space. The members of this organization are professors. The Road to Space conference has just been held.

The last event is worth noting, since this conference is held within the framework of the World Space Week (October 4-10), which this year was dedicated to women in astronautics, as well as within the framework of the Space Science Days held under the auspices of Roscosmos in honor of the launch of the first Earth satellite and the Russian Year of Science and Technology. In general, there are many significant events.

We spoke at all conferences with the scientific results of many years of research, talking about the prospects for education in the field of space medicine. In the future, the department will continue to cooperate with the Center for Aerospace Medicine and Technologies in Moscow on the use of virtual reality methods to assess the reaction rate in zero gravity, the introduction of such new physiological research methods as the assessment of cerebral circulation during immersion, the phenomenon of muscle tone in conditions of model zero gravity, investigation of the reactions of interception of a moving target. We will also continue our educational and educational mission, because it is more interesting to study with space.

A simple example. Physiology textbooks pay very little attention to the fact that all our physiological functions (and their pathophysiological changes) occur under conditions of gravity and are essentially antigravitational. This applies to movement, orientation in space, the usual upright standing and holding the posture, the movement of blood, especially venous blood, the ratio of ventilation and perfusion in the lungs. In general, it makes you be a physicist, biophysicist, mechanic and more and more often look into the textbook of elementary physics.

The project to immerse patients with parkinsonism in a state of ground zero gravity has become a real catalyst for cooperation, in which more and more colleagues from various institutes of PetrSU are involved,

told the scientists of PetrSU L.I. Gerasimova-Meigal and A.Yu. Meigal.

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World Space Week was held from 4 to 10 October - India Education Diary

Physiology

Dr. Ardem Patapoutian awarded Nobel Prize in Physiology or Medicine – Armenian Weekly

(Photo: Office of the High Commissioner for Diaspora Affairs)

Lebanese-Armenian scientist Ardem Patapoutian is one of the two winners of the Nobel Prize in Physiology or Medicine for their discoveries of receptors for touch, heat and bodily movement.

Dr. Patapoutian, a professor of neuroscience at the Scripps Research Institute in La Jolla, California and a Howard Hughes Medical Institute investigator, discovered a new class of sensors that respond to mechanical stimuli in the skin and internal organs.

He was honored alongside David Julius, a UC San Francisco professor of physiology, who identified a sensor in the nerve endings of the skin that responds to heat.

Our ability to sense heat, cold and touch is essential for survival and underpins our interaction with the world around us, the Nobel Assembly wrote in a statement announcing the accolades. The laureates identified critical missing links in our understanding of the complex interplay between our senses and the environment.

Dr. Julius and his team used a key ingredient of chili peppers to identify the gene that makes skin cells capsaicin sensitive. This discovery was a major breakthrough that led the way for scientists to find additional temperature-sensing receptors.

Dr. Patapoutian and his team used a micropipette to poke individual cells and find the sensors that respond to mechanical stimuli such as touch and pressure. In further research, these sensory channels have been shown to regulate physiological processes including blood pressure, respiration and urinary bladder control.

In 1944, Joseph Erlanger and Herbert Gasser received the Nobel Prize in Physiology or Medicine for their discovery of the different types of sensory nerve fibers that react to distinct stimuli, such as painful touch. While scientists have since proven that people perceive changes in their surroundings through highly specialized neurons, a key question long remained unanswered: how are temperature and mechanical stimuli converted into electrical impulses in the nervous system?

This really unlocks one of the secrets of nature, secretary-general of the Nobel Assembly Thomas Perlmann said in announcing the winners. Its actually something that is crucial for our survival, so its a very important and profound discovery.

The pairs findings also have astonishing medical implications, as they are already being used to develop treatments for a wide range of disease conditions, such as chronic back pain, arthritis and migraines.

Dr. Patapoutian said that his phone was on do not disturb when he received the call from Perlmann, who eventually reached his 92-year-old fathers landline. He then called his son at around 2:30AM California time to deliver the news.

Shortly after, the committee released a photo of a delighted Dr. Patapoutian watching the Nobel Prize press conference from his bed with his son Luca: A day to be thankful, tweeted Dr. Patapoutian. This country gave me a chance with a great education and support for basic research.

Dr. Patapoutian, who was born to an Armenian family in Beirut, Lebanon in 1967, came to the United States in 1986. I fell in love with doing basic research. That changed the trajectory of my career, he said in an interview with the New York Times. In Lebanon, I didnt even know about scientists as a career.

The Nobel Prize laureates will each receive a gold medal and 10 million Swedish kronor ($1.14 million).

Lillian Avedian is a staff writer for the Armenian Weekly. Her writing has also been published in the Los Angeles Review of Books, Hetq and the Daily Californian. She is pursuing masters degrees in Journalism and Near Eastern Studies at New York University. A human rights journalist and feminist poet, Lillian's first poetry collection Journey to Tatev was released with Girls on Key Press in spring of 2021.

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Dr. Ardem Patapoutian awarded Nobel Prize in Physiology or Medicine - Armenian Weekly

Physiology

New Nobelist David Julius was a standout from the start – University of California

David Julius, one of todays winners of the 2021 Nobel Prize in Physiology or Medicine, was a standout even as a graduate student at UC Berkeley in the 1970s and 80s, according to one of his mentors, 2013 Nobel laureate Randy Schekman.

Among our most talented Ph.D. students over many decades, David stands out for his originality, focus and determination, said Schekman, a Berkeley professor of molecular and cell biology, adding that, Unlike many people of his level of accomplishment, David is personally sweet and charming and generous in his treatment of others.

Julius, now professor and chair of the Department of Physiology at UC San Francisco and the Morris Herzstein Chair in Molecular Biology and Medicine, shared the prize with Ardem Patapoutian, professor in the Department of Neuroscience at Scripps Research and a Howard Hughes Medical Institute investigator, for their discoveries of receptors for temperature and touch, according to the Nobel Committee 2021in Stockholm, Sweden.

Research on receptors for touch and temperature could lead to better pain killers and, potentially, new treatments for chronic pain. One of Juliuss former postdoctoral students, Diana Bautista, a Berkeley professor of molecular and cell biology and a member of the Helen Wills Neuroscience Institute, has extended this work to look in detail at itch, which is common in such disorders as eczema, and at the impact of chronic inflammation, in general, on the nervous and immune systems.

David is an incredible scientist and mentor, Bautista said. He mentored many students and postdocs and trained us how to approach science using unbiased approaches, to ask the tough questions, and to give back to the scientific community. I am so lucky to have worked with him and am thrilled he received this well-deserved honor.

Julius came to Berkeley in 1977 after graduating from MIT with a B.S. in life sciences and worked with both Schekman and Jeremy Thorner, now a professor emeritus of molecular and cell biology. His thesis focused on the mechanisms of peptide hormone processing and secretion in yeast,Saccharomyces cerevisiae. Schekmans 2013 Nobel Prize in Physiology or Medicine was for work on the secretion process in yeast.

Thorner, with whom Julius primarily worked, is well known for his studies of transmembrane and intracellular signal transduction mechanisms, especially the understanding of how extracellular stimuli control cell growth and division, cell morphology and gene expression work at the biochemical level.

I am just delighted and proud of all that David has accomplished, Thorner said.

According to Schekman, Julius was the first to clone a gene responsible for endoproteolytic cleavage of a pro-hormone precursor, a gene that became the prototype for other proteases that are responsible for processing human hormones, including proinsulin.

After leaving Berkeley in 1984 for a postdoctoral position at Columbia University, Julius cloned the serotonin receptor gene a multi-year struggle, but he eventually succeeded with results that matched his brilliant Ph.D work, Schekman said.

Julius work on serotonin receptors led, after his move to UCSF in 1989, to a focus on the receptors for touch and pain. He subsequently discovered temperature-sensitive ion channel receptors so-called transient receptor potential (TRP), or trip, channels that enable sensory nerve fibers to detect hot or cold temperatures.

Davids work is never derivative, said Allan Basbaum, a frequent scientific collaborator with Julius and the chair of UCSFs Department of Anatomy. Its always groundbreaking, seminal.

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New Nobelist David Julius was a standout from the start - University of California

Physiology

The Nobel Prize in Medicine recognized research on temperature and touch. – The New York Times

The Nobel Prize in Physiology or Medicine was awarded jointly on Monday to David Julius and Ardem Patapoutian, two scientists who independently discovered key mechanisms of how people sense heat, cold, touch and their own bodily movements.

Dr. Julius, a professor of physiology at the University of California, San Francisco, used a key ingredient in hot chili peppers to identify a protein in nerve cells that responds to uncomfortably hot temperatures.

Dr. Patapoutian, a molecular biologist at Scripps Research in La Jolla, Calif., led a team that, by poking individual cells with a tiny pipette, hit upon a receptor that responds to pressure, touch and the positioning of body parts.

After Dr. Juliuss pivotal discovery of a heat-sensing protein in 1997, pharmaceutical companies poured billions of dollars into looking for nonopioid drugs that could dull pain by targeting the receptors. But while research is ongoing, the related treatments have so far run into huge obstacles, scientists said, and interest from drug makers has largely dried up.

Pain and pressure were among the last frontiers of scientists efforts to describe the molecular basis for sensations. The 2004 Nobel Prize in Medicine was given to work clarifying how smell worked. As far back as 1967, the prize was awarded to scientists studying vision.

But unlike smell and sight, the perceptions of pain or touch are not located in an isolated part of the body, and scientists did not even know what molecules to look for. Its been the last main sensory system to fall to molecular analysis, Dr. Julius said at an online briefing on Monday.

The biggest hurdle in Dr. Juliuss work was how to comb through a library of millions of DNA fragments encoding different proteins in the sensory neurons to find the one that reacts to capsaicin, the key component in chili peppers. The solution was to introduce those genes into cells that do not normally respond to capsaicin until one was discovered that made the cells capable of reacting.

In search of the molecular basis for touch, Dr. Patapoutian, too, had to sift through a number of possible genes. One by one, he and his collaborators inactivated genes until they identified the single one that, when disabled, made the cells insensitive to the poke of a tiny pipette.

Dr. Patapoutian said that he gravitated to studying the sense of touch and pain because those systems remained so mysterious. When you find a field thats not well understood, he said, its a great opportunity to dig in.

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The Nobel Prize in Medicine recognized research on temperature and touch. - The New York Times

Physiology

Explained | The 2021 Nobel Prize in Physiology or Medicine – The Hindu

Does the knowledge of nerve impulses which can perceive temperature and pressure when initiated help to treat pain?

The story so far: The 2021 Nobel Prize in Physiology or Medicine was jointly awarded to David Julius, 66, at the University of California, San Francisco, and Ardem Patapoutian, 54, at Scripps Research, La Jolla, California, for their discoveries of receptors for temperature and touch.

Editorial | Sensing heat: On 2021 Nobel Prize in Physiology or Medicine

What is the significance of their work?

The two researchers discovered the molecular mechanism by which our body senses temperature and touch. Being able to do this opens the field for a lot of practical chemistry whereby individual cells and pathways can be tweaked, suppressed or activated to quell pain or sensation. How the body senses external stimuli is among the oldest excursions of natural philosophy. Entire schools of philosophy were based on speculating how the senses influenced the nature of the reality we perceive. Only when physiology developed as an independent discipline and anatomy came into its own did it become widely accepted that specific sensations were the result of different categories of nerves getting stimulated. Thus, a caress or a punch induces cells in our bodies to react differently and convert into specific patterns of electrical stimulation that is then conveyed via the nerves to the central nervous system. Since the Nobel Prizes came to be, at least three of them were for establishing key principles for how sensations travelled along skin and muscle sensory nerve fibres. Much like the length, thickness, material and incident force on their strings elicit specific tones out of a guitar or a piano, there are specific nerve fibre types that in tandem create a response to touch, heat and proprioception, or the sense of our bodys movement and position in space. However, the prominence of molecular biology means that physiology wanted to go a level deeper and find out what specific proteins and which genes are responsible in this symphony of the nerves.

What is the contribution of David Julius towards this?

Capsaicin (8-methyl-N-vanillyl-6-nonenamide), the active component of chili peppers, generates the burning sensation when eating spicy food. Studies on capsaicin showed that when it acted on sensory nerves it induced ionic currents, or the gush of charged particles along a membrane. In the late 1990s, Professor Julius pursued a project to identify a nerve receptor for capsaicin. He thought that understanding the action of capsaicin could provide insights into how the body sensed pain. He and his team went about this by looking for a gene that could induce a response to capsaicin in cells that usually wouldnt react to it. They found one in a novel ion channel protein, later called TRPV1, where TRP stands for transient receptor potential, and VR1 is vanilloid receptor1. They were part of a super family of TRP and it was found that TRPV1 was activated when temperatures were greater than 40 degrees Celsius, which is close to the bodys pain threshold. Several other TRP channels were found, and this ion channel could be activated by various chemical substances, as well as by cold and heat in a way that differs between mammalian species.

What did Ardem Patapoutian find?

Growing up in Beirut as an Armenian, during the Lebanese Civil War, Patapoutian has related stories of being captured by militants at university, before he moved to the United States. Patapoutian and his colleagues were working on how pressure and force affected cells. Following an approach similar to that of Professor Julius, they identified 72 potential genes that could encode an ion channel receptor and trigger sensitivity to mechanical force, and it emerged that one of them coded for a novel ion channel protein, called Piezo1. Via Piezo1, a second gene was discovered and named Piezo2. Sensory neurons were found to express high levels of Piezo2 and further studies firmly established that Piezo1 and Piezo2 are ion channels that are directly activated by the exertion of pressure on cell membranes. The breakthrough by Professor Patapoutian led to a series of papers from his and other groups, demonstrating that the Piezo2 ion channel is essential for the sense of touch. Moreover, Piezo2 was shown to play a key role in proprioception as well as regulate blood pressure, respiration and urinary bladder control. Independently of one another, Professor Julius and Professor Patapoutian used the chemical substance menthol to identify TRPM8, a receptor activated by cold.

What applications do these discoveries have?

Along with the discoveries of specific genes, proteins and pathways, the scientists pioneered experimental methods that allow insight into the structure of these pain and temperature sensors. The challenge for pain relieving drugs is to precisely target regions without causing imbalance in other necessary functions. These scientists work, the Nobel Prize committee said, significantly helped towards reaching that goal.

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Explained | The 2021 Nobel Prize in Physiology or Medicine - The Hindu

Physiology

Charter to establish clinical exercise physiology as a recognised allied health profession in the UK: a call to action – DocWire News

This article was originally published here

BMJ Open Sport Exerc Med. 2021 Sep 21;7(3):e001158. doi: 10.1136/bmjsem-2021-001158. eCollection 2021.

ABSTRACT

The UK population is growing, ageing and becoming increasingly inactive and unfit. Personalised and targeted exercise interventions are beneficial for ageing and the management of chronic and complex conditions. Increasing the uptake of effective exercise and physical activity (PA) interventions is vital to support a healthier society and decrease healthcare costs. Current strategies for exercise and PA at a population level mostly involve self-directed exercise pathways, delivered largely via the fitness industry. Even for those who opt-in and manage to achieve the current recommendations regarding minimum PA, this generic one-size-fits-all approach often fails to demonstrate meaningful physiological and health benefits. Personalised exercise prescription and appropriate exercise testing, monitoring and progression of interventions for individuals with chronic disease should be provided by appropriately trained and recognised exercise healthcare professionals, educated in the cognate disciplines of exercise science (eg, physiology, biomechanics, motor control, psychology). This workforce has operated for >20 years in the Australian public and private healthcare systems. Accredited exercise physiologists (AEPs) are recognised allied health professionals, with demonstrable health and economic benefits. AEPs have knowledge of the risks and benefits of distinct forms of exercise, skills in the personalised prescription and optimal delivery of exercise, and competencies to support sustained PA behavioural change, based on the established scientific evidence. In this charter, we propose a road map for the training, accreditation and promotion of a clinical exercise physiology profession in the UK.

PMID:34631147 | PMC:PMC8458347 | DOI:10.1136/bmjsem-2021-001158

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Charter to establish clinical exercise physiology as a recognised allied health profession in the UK: a call to action - DocWire News

Physiology

Nobel Prize winners 2021: Here’s the complete list of awardees and their contributions – Republic World

Every year in October, the Nobel Committee recognises and awards individualsor organisations for their contributions in specific fields. Fields considered for the awards includephysiology or medicine, physics, chemistry, literature, peace work, and economic science.

The Nobel Prize is given to people who "have conferred the greatest benefit to humankind" bya foundation established by Swedish inventor Alfred Nobel inhis will, read in Stockholm on 30 December 1896.

The Nobel Prizes and the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel have been awarded 609 times to 975 people and organisations between the years 1901 and 2021. Atotal of 943 individuals and 25 organisationsare awarded as some have receivedthe Nobel Prize more than once.

Nobel Peace Prize 2021

Maria Ressa continues to expose abuse of power, use of violence, and growing authoritarianism in her native country, the Philippines by using freedom of expression. On the other hand, for several decades, Dmitry Andreyevich Muratov has defended freedom of speechin Russia amid challenging conditions.

Nobel Prize in Literature 2021

Gurnah is known for hisnovels and a number of short stories that arethemed around the disruption of refugees

Nobel Prize in Physics 2021

Syukuro Manabe,thefirst person to explore the interaction between radiation balance and the vertical transport of air masses,discovered theories to help makeclimate models that assist in detecting weather patterns.

Klaus Hasselmann's methods have proven that global warming is a result of human emissions of carbon dioxide into the atmosphere, andGiorgio Parisi'sdiscoveries makemany different and apparently entirely random phenomena understandable. Their application is not only limited to physics and extends toother fieldsincludingmathematics, biology, neuroscience, and machine learning.

Nobel Prize in Chemistry 2021

List and MacMillan have been recognised for their contribution in making molecular construction easier by inventing a tool that helps in catalysis for producing asymmetric molecules.

Nobel Prize in Physiology or Medicine 2021

Julius and Patapotian's breakthrough discoveries launched intense research activities leading to a rapid increase in the understanding of how the humannervous system senses heat, cold, and mechanical stimuli.

Sveriges Riksbank Prize in Economic Sciences

The three laureates havenew insights about the labour market and have shown what conclusions about cause and effect can be drawn from natural experiments. Their approach has spread to other fields and has revolutionised empirical research.

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Nobel Prize winners 2021: Here's the complete list of awardees and their contributions - Republic World

Physiology

Jeff Ramirez to be Inducted into American Academy of Nursing – gonzaga.edu

SPOKANE, Wash. Jeffery Ramirez, Ph.D., a psychiatric nurse practitioner and a professor of nursing in the School of Nursing and Human Physiology at Gonzaga University, has been selected to become a Fellow of the American Academy of Nursing.

Professor Ramirez and the other 2021 inductees will be recognized for their significant contributions to health care at the Academys annual Health Policy Conference, Oct. 7-9. This years conference and induction ceremony is offered in a hybrid format, allowing attendees to participate in-person (at the Marriott Marquis in Washington, D.C.) or virtually, allowing for maximum attendance through an inclusive format where colleagues, friends, and family members who may not be able to attend the event in person are able to participate. This years induction ceremony will feature personalized video vignettes and live streaming of each inductee.

Induction into the Academy is a significant milestone in a nurse leaders career in which their accomplishments are honored by their colleagues within and outside the profession. Fellows are selected based on their contributions and impact to advance the publics health.

The Academy is an honor society that recognizes nursings most accomplished leaders in policy, research, practice, administration, and academia. Academy Fellows, from nearly 40 countries, hold a wide variety of roles influencing health care. Induction into the Fellowship represents more than recognition of ones accomplishments within the nursing profession. Fellows contribute their collective expertise to the Academy, engaging with health leaders nationally and globally to improve health and achieve health equity by impacting policy through nursing leadership, innovation, and science.

Through a competitive, rigorous application process, the Academys Fellow Selection Committee reviewed hundreds of applications to select the 2021 Fellows. Ramirez was one of 225 individuals selected to be inducted into the 2021 class, which represents 38 states, the District of Columbia, and 18 countries.

Ramirez also was inducted as a Fellow in the American Association of Nurse Practitioners (FAANP) in 2019 and a Distinguished Fellow in the National Academies of Practice in 2020. He is the first nurse practitioner faculty member from Gonzaga to receive these honors.

Dr. Ramirez has held hospital leadership positions as a Nurse Manager, Clinical Nurse Specialist, and Director of Quality Management. He shared his clinical expertise in psychiatric nursing by consulting throughout the country advocating for system changes to improve the care and treatment of psychiatric hospitalized patients. He has been an invited speaker at the local, state, and national level. He has served on expert nursing panels, state and national nursing professional organization boards.

Professor Ramirez is a recognized leader in psychiatric-mental health nurse practitioner (PMHNP) education and has educated PMHNPs to serve in rural and underserved communities in multiple states. He has held educational leadership positions including as lead faculty for the PMHNP program, chairperson for the nursing department and program director for the Doctor of Practice.

I am honored to be chosen to this distinguished and respected academy, Ramirez said. This is certainly one of the greatest recognitions a nursing scholar can receive. I am looking forward to joining this esteemed group of nursing leaders and carrying out the mission of the American Academy of Nursing and improving health through leadership and innovations.

For more information, please contact Professor Ramirez at (509) 313-6484.

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Jeff Ramirez to be Inducted into American Academy of Nursing - gonzaga.edu

Physiology

Busted body clocks mess with fight or flight response – Futurity: Research News

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New research in mice digs into how the bodys internal clocks manage release of important hormones.

For humans and animals, many aspects of normal behavior and physiology rely on the proper functioning of the bodys circadian clocks.

for a normal hormone rhythm to proceed, you need clocks in both the central pacemaker and this downstream region to work in tandem.

Heres how its supposed to work: Your brain sends signals to your body to release different hormones at certain times of the day. For example, you get a boost of the hormone cortisolnatures built-in alarm systemright before you usually wake up.

But hormone release actually relies on the interconnected activity of clocks in more than one part of the brain.

The new research shows how daily release of glucocorticoids depends on coordinated clock-gene and neuronal activity rhythms in neurons found in two parts of the hypothalamus, the suprachiasmatic nucleus (SCN) and paraventricular nucleus (PVN).

The new study, conducted with freely behaving mice, appears in Nature Communications.

Normal behavior and physiology depends on a near 24-hour circadian release of various hormones, says Jeff Jones, who led the study as a postdoctoral research scholar in biology atWashington University in St. Louis and recently started work as an assistant professor of biology at Texas A&M University.

When hormone release is disrupted, it can lead to numerous pathologies, including affective disorders like anxiety and depression and metabolic disorders like diabetes and obesity.

We wanted to understand how signals from the central biological clocka tiny brain area called the SCNare decoded by the rest of the brain to generate these diverse circadian rhythms in hormone release, says Jones, who worked with Erik Herzog, a professor at Washington University and senior author of the new study.

The daily timing of hormone release is controlled by the SCN. Located in the hypothalamus, just above where the optic nerves cross, neurons in the SCN send daily signals that are decoded in other parts of the brain that talk to the adrenal glands and the bodys endocrine system.

Cortisol in humans (corticosterone in mice) is more typically known as a stress hormone involved in the fight or flight response, Jones says. But the stress of waking up and preparing for the day is one of the biggest regular stressors to the body. Having a huge amount of this glucocorticoid released right as you wake up seems to help you gear up for the day.

Or for the night, if youre a mouse.

The same hormones that help humans prepare for dealing with the morning commute or a challenging work day also help mice meet their nightly step goals on the running wheel.

Using a novel neuronal recording approach, Jones and Herzog recorded brain activity in individual mice for up to two weeks at a time.

Recording activity from identified types of neurons for such a long period of time is difficult and data intensive, Herzog says. Jeff pioneered these methods for long-term, real-time observations in behaving animals.

Using information about each mouses daily rest-activity and corticosterone secretion, along with gene expression and electrical activity of targeted neurons in their brains, the scientists discovered a critical circuit between the SCN and neurons in the PVN that produce the hormone that triggers release of glucocorticoids.

Turns out, its not enough for the neurons in the SCN to send out daily signals; the local clock in the PVN neurons also has to be working properly in order to produce coordinated daily rhythms in hormone release.

Experiments that eliminated a clock gene in the circadian-signal-receiving area of the brain broke the regular daily cycle.

Theres certain groups of neurons in the SCN that communicate timing information to groups of neurons in the PVN that regulate daily hormone release, Jones says. And for a normal hormone rhythm to proceed, you need clocks in both the central pacemaker and this downstream region to work in tandem.

The findings in mice could have implications for humans down the road, Jones says. Future therapies for cortisol-related diseases and genetic conditions in humans will need to take into account the importance of a second internal clock.

Source: Washington University in St. Louis

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Busted body clocks mess with fight or flight response - Futurity: Research News

Physiology

Weed goes off script to resist herbicides – EurekAlert

image:University of Illinois researchers (from left) Seth Strom, Dean Riechers, and Crystal Concepcion discovered multiple ways waterhemp is devising new biochemical strategies to evade herbicide control. view more

Credit: Lauren Quinn, University of Illinois

URBANA, Ill. Cementing waterhemps reputation as a hard-to-kill weed in corn and soybean production systems, University of Illinois researchers have now documented the weed deviating from standard detoxification strategies to resist an herbicide that has never been commercialized.

The chemical in question, syncarpic acid-3 (SA3), is the great-great grandfather of the HPPD-inhibiting herbicide Callisto. SA3 has never been used in corn because it has the rather unfortunate effect of killing the crop along with the weeds. Corn can tolerate Callisto and other herbicides because it has a robust detoxification system to neutralize and cordon off the harmful chemical. But corns neutralizing systems dont work on SA3.

Weeds like waterhemp typically evolve detoxification systems that mimic corns. Thats why it's especially surprising that HPPD-resistant waterhemp can detoxify SA3.

"This is probably the first known example where waterhemp has evolved a detox mechanism that a crop doesn't have. Its using a completely different mechanism, adding to the complexity of controlling this weed, says Dean Riechers, professor in the Department of Crop Sciences at U of I and co-author on a new study in New Phytologist.

The discovery means waterhemp could theoretically be resistant to new herbicide products before they even hit the shelves.

Weve always known metabolic resistance is dangerous because it could confer resistance to a yet-to-be-discovered herbicide. Weve just shown that this is a reality, Riechers says. Companies don't want to invest 10-15 years in developing a new herbicide, patent and release it, and find it doesn't work on day one. Our research reinforces that we need to rely more on non-chemical control methods and make sure weeds don't go to seed.

Riechers and postdoctoral associate Crystal Concepcion traced the biochemical reactions inside resistant waterhemp plants when treated with SA3.

Detoxification of herbicides and other toxic compounds usually happens in distinct phases. The first involves a group of enzymes known as p450s that remove electrons from toxic compounds, making them less reactive inside plant cells. But in resistant waterhemp, the opposite happened: electrons were added to SA3 molecules.

Phase-two enzymes known as GSTs are normally not activated for Callisto because p450s get the job done so quickly and efficiently in corn. But for SA3, GSTs did the heavy lifting of detoxification.

Along with the removal of a water molecule in the first phase, the addition of those electrons prepared the phase-two GST enzymes to detoxify SA3, Concepcion says. Its surprising because not only did the phase-one reactions not proceed as expected, we didnt even anticipate GSTs to be involved for this class of herbicides. We dont see corn preparing chemicals for attack by GSTs. This is very, very rare for herbicides.

Riechers says this deviation from standard biochemical detoxification patterns represents something truly novel and potentially damaging for crop producers. Its definitely challenging, he says.

The research group is on a roll with unexpected findings.

Scientists have known for years that corn, soybeans, and sorghum use GSTs to metabolize S-metolachlor, a soil-applied herbicide offering residual weed control. Therefore, they assumed waterhemp used the same mechanism to detoxify the chemical. But in a recent paper, published in Plant and Cell Physiology, Riechers research team documented another example of waterhemp going off script.

In this case, we were thinking it was GSTs all the way. But the data told us otherwise. The metabolomics approach we took informed us that GSTs arent the main mechanism to detoxify S-metolachlor in resistant waterhemp. Its actually p450s, Riechers says.

Last year, Riechers worked with former doctoral student Seth Strom, extension weed scientist and crop sciences professor Aaron Hager, and others to show waterhemp employs both p450s and GSTs in detoxifying Group 15 herbicides. But when they dug deeper in the new Plant and Cell Physiology study, the researchers found GST enzyme activity was detectable in both resistant and sensitive waterhemp but much lower than in corn. In contrast, p450 activity in resistant waterhemp was 20 times greater than in the crop and in sensitive waterhemp.

Studying resistance to soil-applied herbicides like S-metolachlor can be challenging, especially in waterhemp where there were not any templates or previous methods to follow. Developing methods to understand S-metolachlor resistance was worth every minute knowing that results could eventually help provide solutions for growers, says Strom, now a field R&D scientist at Syngenta Crop Protection.

Both studies demonstrate that waterhemp is done relying on corn for detoxification cues, and is evolving its own ways of conquering herbicides.

The New Phytologist article is available at https://doi.org/10.1111/nph.17708.The Plant and Cell Physiology article is available at https://doi.org/10.1093/pcp/pcab132.

Both projects were funded in part by Syngenta.

The Department of Crop Sciences is in the College of Agricultural, Consumer and Environmental Sciences at the University of Illinois at Urbana Champaign.

Resistance to a nonselective 4-hydroxyphenylpyruvate dioxygenase-inhibiting herbicide via novel reductiondehydrationglutathione conjugation in Amaranthus tuberculatus

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Weed goes off script to resist herbicides - EurekAlert