Researchers Discover New Mechanism for Rapid Liver Regeneration to Restore Damaged Livers

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Researchers at the National Cancer Research Centre in Spain (CNIO) have discovered a mechanism that is triggered just minutes after acute liver damage occurs—and it could lead to treatments for those with severe liver problems.

The avenues for future treatments of liver damage include a diet enriched with the amino acid glutamate.

“Glutamate supplementation can promote liver regeneration and benefit patients in recovery following hepatectomy or awaiting a transplant,” wrote the authors in a paper published in ‘Nature’.

The liver is a vital organ, crucial to digestion, metabolism, and the elimination of toxins. It has a unique ability to regenerate, which allows it to replace liver cells damaged by the very toxins that these cells eliminate.

However, the liver stops regenerating in cases of diseases that involve chronic liver damage–such as cirrhosis—and such diseases are becoming increasingly prevalent, associated with poor dietary habits or alcohol consumption. So activating liver regeneration is key to treating the disease.

Learning to activate liver regeneration is therefore a priority today, to benefit patients with liver damage and also those who’ve had part of their liver cut out to remove a tumor.

The research has discovered in animal models this previously unknown mechanism of liver regeneration. It is a process that is triggered very quickly, just a few minutes after acute liver damage occurs, with the amino acid glutamate playing a key role.

“Our results describe a fundamental and universal mechanism that allows the liver to regenerate after acute damage,” explained Nabil Djouder, head of the CNIO Growth Factors, Nutrients and Cancer Group and senior author of the study.

A “complex and ingenious” perspective on liver regeneration

Liver regeneration was known to occur through the proliferation of liver cells, known as hepatocytes. However, the molecular mechanisms involved were not fully understood. This current discovery is very novel, as it describes communication between two different organs, the liver and bone marrow, involving the immune system, according to a CINO news release.

The results show that liver and bone marrow are interconnected by glutamate. After acute liver damage, liver cells, called hepatocytes, produce glutamate and send it into the bloodstream; through the blood, glutamate reaches the bone marrow, inside the bones, where it activates monocytes, a type of immune system cell. Monocytes then travel to the liver and along the way become macrophages – also immune cells. The presence of glutamate reprograms the metabolism of macrophages, and these consequently begin to secrete a growth factor that leads to an increase in hepatocyte production.

In other words, a rapid chain of events allows glutamate to trigger liver regeneration in just minutes, through changes in the macrophage metabolism. It is, says Djouder, “a new, complex and ingenious perspective on how the liver stimulates its own regeneration.”

The research also clarifies a previously unanswered question: how the various areas of the liver are coordinated during regeneration. In the liver, there are different types of hepatocytes, organized in different areas; the hepatocytes in each area perform specific metabolic functions. The study reveals that hepatocytes producing a protein known as glutamine synthetase, which regulates glutamate levels, play a key role in regeneration.

According to the CNIO group, when glutamine synthetase is inhibited, there is more glutamate in circulation, which accelerates liver regeneration. This is what happens when the liver suffers acute damage: glutamine synthase activity decreases, blood glutamate increases, and from there, the connection with the bone marrow is established, reprogramming macrophages and stimulating hepatocyte proliferation.

Possible therapeutic applications

The experiments have been carried out in mice, but the results have been tested with bioinformatics tools, using databases of mouse and human hepatocytes.

According to Djouder, “dietary glutamate supplementation may simply be recommended in the future after liver extirpation, and also to reduce liver damage caused by cirrhosis.”

The first author of the paper, CNIO researcher María del Mar Rigual also wants future research to explore using glutamate supplements in humans who have undergone liver resection for tumor removal. Researchers Discover New Mechanism for Rapid Liver Regeneration to Restore Damaged Livers

Read More........→April 17, 2025

Nasa's SOFIA finds water on sunlit surface of Moon

Nasa’s Stratospheric Observatory for Infrared Astronomy (SOFIA) – a telescope operating from an aircraft - has confirmed, for the first time, water on the sunlit surface of the Moon. This discovery indicates that water may be distributed across the lunar surface, and not limited to cold, shadowed places, Nasa revealed today.

SOFIA, a joint project of Nasa and the German Aerospace Centre. has detected water molecules (H2O) in Clavius Crater, one of the largest craters visible from Earth, located in the Moon’s southern hemisphere, the US space agency said. While previous observations of the Moon’s surface had detected some form of hydrogen, Nasa said, they were unable to distinguish between water and its close chemical relative, hydroxyl (OH). 

Data from this location reveal water in concentrations of 100 to 412 parts per million – roughly equivalent to a 12-ounce bottle of water – trapped in a cubic meter of soil spread across the lunar surface. The results are published in the latest issue of Nature Astronomy.

“We had indications that H2O – the familiar water we know – might be present on the sunlit side of the Moon,” said Paul Hertz, director of the Astrophysics Division in the Science Mission Directorate at NASA Headquarters in Washington. “Now we know it is there. This discovery challenges our understanding of the lunar surface and raises intriguing questions about resources relevant for deep space exploration.”

In comparison, the Sahara desert has 100 times the amount of water than what SOFIA detected in the lunar soil. Despite the small amounts, the discovery raises new questions about how water is created and how it persists on the harsh, airless lunar surface.

Since water is a precious resource in deep space and a key ingredient of life, Nasa is using its Artemis programme to study the presence of water on the Moon ahead of sending the first woman and next man to the lunar surface in 2024 with a view to establishing a sustainable human presence there by the end of the decade.

Under SOFIA’s results build on years of previous research examining the presence of water on the Moon. When the Apollo astronauts first returned from the Moon in 1969, it was thought to be completely dry. Orbital and impactor missions over the past 20 years, such as Nasa’s Lunar Crater Observation and Sensing Satellite, confirmed ice in permanently shadowed craters around the Moon’s poles.

Meanwhile, several spacecraft, including the Cassini mission and Deep Impact comet mission, as well as the Indian Space Research Organisation’s Chandrayaan-1 mission, and Nasa’s ground-based Infrared Telescope Facility, looked broadly across the lunar surface and found evidence of hydration in sunnier regions. Yet those missions were unable to definitively distinguish the form in which it was present – either H2O or OH.

“Prior to the SOFIA observations, we knew there was some kind of hydration,” said Casey Honniball, the lead author who published the results from her graduate thesis work at the University of Hawaii at Manoa in Honolulu. “But we didn’t know how much, if any, was actually water molecules – like we drink every day – or something more like drain cleaner.”

Scientists using Nasa’s telescope on an airplane, the Stratospheric Observatory for Infrared Astronomy, discovered water on a sunlit surface of the Moon for the first time. 

SOFIA is a modified Boeing 747SP aircraft that allows astronomers to study the solar system and beyond in ways that are not possible with ground-based telescopes. Molecular water, H2O, was found in Clavius Crater, one of the largest craters visible from Earth in the Moon’s southern hemisphere. This discovery indicates that water may be distributed across the lunar surface, and not limited to cold, shadowed places.

SOFIA offered a new means of looking at the Moon. Flying at altitudes of up to 45,000 feet, this modified Boeing 747SP jetliner with a 106-inch diameter telescope reaches above 99 per cent of the water vapor in Earth’s atmosphere to get a clearer view of the infrared universe. Using its Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST), SOFIA was able to pick up the specific wavelength unique to water molecules, at 6.1 microns, and discovered a relatively surprising concentration in sunny Clavius Crater.

“Without a thick atmosphere, water on the sunlit lunar surface should just be lost to space,” said Honniball, who is now a postdoctoral fellow at Nasa’s Goddard Space Flight Center in Greenbelt, Maryland. “Yet somehow we’re seeing it. Something is generating the water, and something must be trapping it there.”

Several forces could be at play in the delivery or creation of this water. Micrometeorites raining down on the lunar surface, carrying small amounts of water, could deposit the water on the lunar surface upon impact. Another possibility is there could be a two-step process whereby the Sun’s solar wind delivers hydrogen to the lunar surface and causes a chemical reaction with oxygen-bearing minerals in the soil to create hydroxyl. Meanwhile, radiation from the bombardment of micrometeorites could be transforming that hydroxyl into water.

How the water then gets stored – making it possible to accumulate – also raises some intriguing questions. The water could be trapped into tiny beadlike structures in the soil that form out of the high heat created by micrometeorite impacts. Another possibility is that the water could be hidden between grains of lunar soil and sheltered from the sunlight – potentially making it a bit more accessible than water trapped in beadlike structures.

For a mission designed to look at distant, dim objects such as black holes, star clusters, and galaxies, SOFIA’s spotlight on Earth’s nearest and brightest neighbor was a departure from business as usual. The telescope operators typically use a guide camera to track stars, keeping the telescope locked steadily on its observing target. But the Moon is so close and bright that it fills the guide camera’s entire field of view. With no stars visible, it was unclear if the telescope could reliably track the Moon. To determine this, in August 2018, the operators decided to try a test observation.

“It was, in fact, the first time SOFIA has looked at the Moon, and we weren’t even completely sure if we would get reliable data, but questions about the Moon’s water compelled us to try,” said Naseem Rangwala, SOFIA’s project scientist at Nasa's Ames Research Center in California's Silicon Valley. “It’s incredible that this discovery came out of what was essentially a test, and now that we know we can do this, we’re planning more flights to do more observations.”

SOFIA’s follow-up flights will look for water in additional sunlit locations and during different lunar phases to learn more about how the water is produced, stored, and moved across the Moon. The data will add to the work of future Moon missions, such as Nasa’s Volatiles Investigating Polar Exploration Rover (VIPER), to create the first water resource maps of the Moon for future human space exploration.

In the same issue of Nature Astronomy, scientists have published a paper using theoretical models and Nasa's Lunar Reconnaissance Orbiter data, pointing out that water could be trapped in small shadows, where temperatures stay below freezing, across more of the Moon than currently expected. The results can be found here. 

“Water is a valuable resource, for both scientific purposes and for use by our explorers,” said Jacob Bleacher, chief exploration scientist for Nasa’s Human Exploration and Operations Mission Directorate. “If we can use the resources at the Moon, then we can carry less water and more equipment to help enable new scientific discoveries.”SOFIA is a joint project of Nasa and the German Aerospace Center. Ames manages the SOFIA programme, science, and mission operations in cooperation with the Universities Space Research Association, headquartered in Columbia, Maryland, and the German SOFIA Institute at the University of Stuttgart. The aircraft is maintained and operated by Nasa’s Armstrong Flight Research Center Building 703, in Palmdale, California. Source: https://www.domain-b.com/

Read More........→October 30, 2020