PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Study reveals mechanism that activates glucose production in the liver in response to stress

In addition to providing a detailed description of the morphology of hepatic nerves, the study led by Brazilians showed that the increase in blood sugar was activated by a protein called CREB.

2024-09-10
(Press-News.org) A study led by Brazilian researchers has produced a detailed description of the morphology of the nerves in the liver and how they control production of glucose when the organism is under stress. This process is known as hepatic gluconeogenesis. It is a key metabolic function of the liver that helps maintain a normal blood sugar level, especially when fasting and at times of high energy needs. 

An article on the study, which entailed experiments with mice, is published in the journal Metabolism. According to the authors, the sympathetic nerves that stimulate the release of noradrenaline in the liver helped increase blood sugar by activating gluconeogenesis in response to cold. Specific molecules – the protein CREB and its coactivator CRTC2 – that have never been studied in depth were involved in this activation. 
Noradrenaline (also called norepinephrine) is a neurotransmitter that plays a key role in rapid responses to stress or danger, raising heart rate, blood pressure and the release of glucose from energy reserves. Most studies in the scientific literature regarding the regulation of glucose synthesis by the liver focus on the action of hormones in the pancreas and adrenal glands.

A detailed analysis of these mechanisms is crucial to a better understanding of the disruptions of physiological processes that lead to metabolic diseases such as diabetes and obesity. The findings of the study therefore point to further opportunities for research on the same topic, especially situations involving alterations to the sympathetic nervous system, such as high blood pressure and hepatic steatosis (fatty liver disease). 

“The originality of our study lies in showing that the central nervous system, via sympathetic nerves, can control CREB and activate de novo glucose production by the liver if extra energy is required. We describe the anatomy of the innervation in the liver using a methodology never used before in Brazil,” Luiz Carlos Navegantes, a professor in the Department of Physiology at the University of São Paulo’s Ribeirão Preto Medical School (FMRP-USP) and corresponding author of the article, told Agência FAPESP.

The researchers deployed a technique known as 3DISCO (three-dimensional imaging of solvent-cleared organs), a histology method that makes biological samples more transparent using organic solvents and produces a 3D image with the nerves clearly visible.
The study was supported by FAPESP via a Thematic Project, as well as master’s (19/26583-9 and 19/05900-6) and PhD scholarships awarded to biologist Henrique Jorge Novaes Morgan), first author of the article. Morgan won the Álvaro Osório de Almeida Prize awarded by the Brazilian Society of Physiology (SBFis) in 2021. 

The other co-authors included researchers affiliated with the University of Oxford and Francis Crick Institute in the United Kingdom, and Marc Montminy at the Salk Institute for Biological Studies in the United States. The latter discovered CREB and elucidated its role in energy metabolism regulation, pointing to potential targets for drugs to combat insulin resistance, diabetes and obesity.

Methodology

The scientists used 3D immunoimaging to analyze the distribution of sympathetic nerves in the mouse liver, observing a dense innervation comprising thick primary nerve fibers with smaller branches that did not make direct contact with hepatocytes (liver cells).

To investigate the physiological role of this innervation, the mice were exposed to cold (4 °C) for up to six hours. Cold stress activated CREB/CRTC2 via calcium (Ca2+) signaling to assure the supply of glucose to muscles and keep the body warm.

“Continuing the groundbreaking research of Renato Hélios Migliorini, who founded our lab and showed in the 1980s that the nervous system was capable of activating gluconeogenesis, we set out to understand what happened at the molecular level. To this end, we analyzed mice from which we chemically or surgically removed this innervation in the liver, and transgenic mice without CRTC2. In these cases, gluconeogenesis did not occur in response to cold. In other words, mice without the nerves or the CREB coactivator were unable to produce glucose in response to stress. These findings added a novel component to the science of gluconeogenesis,” Navegantes said. 

About São Paulo Research Foundation (FAPESP)
The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.
 

END


ELSE PRESS RELEASES FROM THIS DATE:

Aumolertinib maintenance after chemoradiotherapy in stage III non-small cell lung cancer improves PFS compared to placebo

Aumolertinib maintenance after chemoradiotherapy in stage III non-small cell lung cancer improves PFS compared to placebo
2024-09-10
(San Diego, Calif.--September 9, 2024, 10:05 a.m.) -- The epidermal growth factor receptor tyrosine kinase inhibitor aumolertinib demonstrated improved progression-free survival compared to placebo without any significant new adverse reactions, according to data from the POLESTAR study presented today at the International Association for the Study of Lung Cancer 2024 World Conference on Lung Cancer. Consolidation therapy with durvalumab is established as the standard of care for patients who do not experience disease progression following concurrent chemoradiotherapy. However, it is unknown what the specific benefit ...

Weight loss of up to 13% achieved in three months with once-a-day tablet, phase 1 trial finds

2024-09-10
Individuals who received a once-a-day oral weight loss drug lost up to 13% of their body weight over three months, the annual meeting of the European Association for the Study of Diabetes (EASD) in Madrid, Spain (9-13 September) will hear. Amycretin, which is being developed by the Danish pharmaceutical company Novo Nordisk A/S, mimics the action of two peptide hormones in one single molecule. Amycretin is both an amylin and glucagon-like peptide-1 (GLP-1) receptor agonist. Both of these play a key role in appetite regulation ...

Time-restricted eating improves blood sugar control in adults at risk of type 2 diabetes regardless of time of day

2024-09-10
Restricting the eating window to 8 hours a day significantly improves blood glucose control in adults at risk of type 2 diabetes irrespective of whether it is earlier or later in the day, according to a randomised crossover trial to be presented at this year’s Annual Meeting of The European Association for the Study of Diabetes (EASD), Madrid (9-13 Sept). “Our study found that restricting eating to a window of 8 hours per day significantly improved the daily time spent in the normal blood glucose range and reduced fluctuations in blood glucose levels. However, altering the 8-hour restricted eating period ...

Individuals with complications of diabetes are at higher risk of gum disease, Danish study finds

2024-09-10
Gum disease is more common in individuals with microvascular complications of diabetes, new research being presented at the annual meeting of the European Association for the Study of Diabetes (EASD) in Madrid, Spain (9-13 September) and published in The Journal of Dental Research has found. Periodontitis is a chronic inflammatory disease that affects the gums and the bones supporting the teeth. It is caused by the accumulation of bacterial plaque, and if left untreated, it can lead to the destruction of the tissues that hold the teeth in place, ultimately resulting in tooth loss. “This tooth loss can affect essential functions like chewing and speaking, while ...

Weight loss drug liraglutide is safe and effective in children under 12, study finds

2024-09-10
The obesity medication liraglutide is safe and effective in children aged 6 to <12 years, new research being presented at the annual meeting of the European Association for the Study of Diabetes (EASD) in Madrid, Spain (9-13 September), and published simultaneously in the New England Journal of Medicine (NEJM), has found. Childen aged six to <12 years who took liraglutide for just over a year experienced a reduction in BMI of 7.4% compared to placebo and experienced improvements in blood pressure and blood sugar control. The results of ...

Chemotherapy before surgery helps patients with nose and sinus cancer avoid debilitating eye and bone removal

Chemotherapy before surgery helps patients with nose and sinus cancer avoid debilitating eye and bone removal
2024-09-10
Results from a clinical trial by the ECOG-ACRIN Cancer Research Group (ECOG-ACRIN) show a striking improvement for patients who received chemotherapy before surgery to remove advanced squamous cell-type cancer of the nose or sinus. The European Society of Medical Oncology is highlighting the trial at its ESMO Congress 2024 in Barcelona, Spain. Surgery is required for these patients but at a high physical cost. Patients enrolled in this trial had signs that surgery would result in loss of the eye, the base of the skull bone, or both. However, in the randomized prospective trial EA3163, patients receiving chemotherapy ...

The glug of it all

2024-09-10
As Rohit Velankar, now a senior at Fox Chapel Area High School, poured juice into a glass, he could feel that the rhythmic glug, glug, glug was flexing the walls of the carton. Rohit pondered the sound, and wondered if a container’s elasticity influenced the way its fluid drained. He initially sought the answer to his question for his science fair project, but it spiraled into something more when he teamed up with his father, Sachin Velankar, a professor of chemical and petroleum engineering at the University of Pittsburgh Swanson School of Engineering.  They set up an experiment ...

UTA to build netted drone facility in Fort Worth

UTA to build netted drone facility in Fort Worth
2024-09-10
The University of Texas at Arlington is expanding its research and innovation capabilities by building a $2.3 million, state-of-the-art outdoor netted drone facility. The Maverick Autonomous Vehicle Research Center (MAVRC) will be located at the UT Arlington Research Institute (UTARI) in Fort Worth, with a planned completion date of January 2025. “MAVRC will significantly and positively impact UTA’s presence in the region by supporting the university-industry-government-community ecosystem focused ...

Streamlining energy regulations on Native American reservations could help alleviate poverty

2024-09-10
MADISON–Land was once set aside as Native American reservations because it was undesirable and low in resources, but now interested Native Americans may have economic leverage in the growing industry of clean energy. A team of researchers led by UW–Madison professors Dominic Parker and Sarah Johnston quantified the economic potential of wind and solar energy projects on these lands and discussed the regulatory barriers for tribes wishing to tap into it. “This is the first comprehensive ...

UT microbiologist Wilhelm honored as Fellow of the Royal Society of Canada

UT microbiologist Wilhelm honored as Fellow of the Royal Society of Canada
2024-09-10
Steven Wilhelm joins a distinguished roster this year with his election as a fellow of the Royal Society of Canada (RSC) Academy of Science. This recognition is the RSC’s highest honor in areas of arts, social sciences, humanities, and science. “The RSC inducts fellows to help them build a better future in Canada and the world. As a native Canadian, this honor is the pinnacle of what I could have hoped for in my career,” said Wilhelm, the Kenneth and Blaire Mossman Professor in UT’s Department of Microbiology. “It also provides an opportunity for me to work with my collaborators ...

LAST 30 PRESS RELEASES:

SwRI-developed instruments will study potential habitability of Jupiter’s moon Europa

Proposed scoring system may enhance equity in organ transplantation, increase transplant rates and improve patient survival

Survivors of childhood brain cancer are more likely to be held back in school

Updating offshore turbine designs to reflect storms’ complexity is key

Hospital strain during the COVID-19 pandemic and outcomes in older racial and ethnic minority adults

Scientists unveils key role of “selfish DNA” in early human development

Bonobos may be more vulnerable than previously thought, suggests genetics study

Scripps Research scientists discover chemical probes for previously “undruggable” cancer target

Giant Magellan telescope begins primary mirror support system testing

Experimental cancer drug eliminates bone metastases caused by breast cancer in lab models

Political candidates who fight climate change stand to benefit in election

Stand up to Cancer announces new grants supporting pioneering research in six cancer types

Researchers awarded $1.3M to help military Veterans battling Acute Myeloid Leukemia

New hub for high-energy astrophysics — CTAO Science Data Management Centre opens at DESY in Zeuthen

JMIR publications CEO and Executive Editor Gunther Eysenbach achieves #1 ranking as most cited researcher in Medical Informatics for fifth consecutive year

ERC grant for groundbreaking wearable health tech

NIH announces winners of prize competition to improve postpartum maternal health and health equity through innovative diagnostics

APS and SPR honor Dr. Cynthia F. Bearer with the 2025 Mary Ellen Avery Neonatal Research Award

Election delays and voter trust

US air pollution monitoring network has gaps in coverage, say researchers

Continuous monitoring of fatigue in factory workers

Farmer ants’ wearable bacteria

Political polarization and trust

Study uncovers how silkworm moth's odor detection may improve robotics

New study links obesity to elevated hypertension risk among young middle eastern women

How ‘vaccinating’ plants could reduce pesticide use and secure global food supplies

Seven new frog species discovered in Madagascar: sounds like something from Star Trek

New temperatures in two thirds of key tropical forest

Fearful memories of others seen in mouse brain

Rangers lead ground-breaking effort to monitor Uganda's lion population in critical stronghold

[Press-News.org] Study reveals mechanism that activates glucose production in the liver in response to stress
In addition to providing a detailed description of the morphology of hepatic nerves, the study led by Brazilians showed that the increase in blood sugar was activated by a protein called CREB.