Newfound mechanism rewires cellular energy processing for drastic weight loss: Study

Washington: Mice genetically engineered to lack the ability to make the amino acid
cysteine
, and fed a cysteine-free
diet
, lost 30 per cent of their body weight in just one week, a new study shows.
Published online May 21 in Nature, the work found that cysteine depletion disrupts the normal metabolic pathways mammalian cells use to convert food into energy, forcing the animals to rapidly burn fat stores in a futile attempt to meet energy demands.
Led by researchers at
NYU Grossman School of Medicine
, the study reveals key details about how cells process fuels like carbohydrates and fats (
metabolism
), and how cysteine depletion affects tissues.
Experiments showed that lowering cysteine levels caused a drop in levels of the small molecule called
coenzyme A
(CoA), which rendered inefficient mechanisms that convert carbohydrates and fats into energy.
Despite CoA being involved in more than 100 intermediate metabolic reactions and serving as a partner (cofactor) for 4% of all enzymes in the body, scientists had previously been unable to study its function directly.
This is because mice with defective CoA synthesis typically do not survive beyond three weeks of age. The current findings detail, for the first time, how CoA shapes metabolism in adult mice.
"Our surprising findings reveal that low cysteine levels triggered rapid
fat loss
in our study mice by activating a network of interconnected biological pathways," said co-senior study author Evgeny Nudler, PhD, the Julie Wilson Anderson Professor in the Department of Biochemistry and Molecular Pharmacology at NYU Grossman School of Medicine, and an investigator with the Howard Hughes Medical Institute.
"While driving
weight loss
in the clinic remains a key future mission, we are most excited for the moment about the profound, fundamental aspects of metabolism revealed in this study," added Dr. Nudler.
The current finding does not immediately suggest a new approach to weight loss, the authors caution, as cysteine is found in nearly all foods.
Achieving a truly cysteine-free diet would require patients to consume a specially formulated solution that would be challenging for most.
Moreover, because cysteine is involved in numerous cellular pathways, eliminating it -- such as through a drug that inhibits cysteine production -- could make organs more vulnerable to everyday toxins, including medications.
That said, the study authors say it is worth considering that fruits, vegetables, and legumes contain much lower levels of cysteine and its precursor, the sulfur-containing amino acid methionine, than red meat. (ANI)

Try Our AI Features

Explore what Daily8 AI can do for you:

Learn with AIFact CheckingText to SpeechAI Summary

Related Articles

The Hindu

2 days ago

• The Hindu

Warming will cut yield of staple crops even post-adaptation: study

For every 1° C rise in average temperature worldwide, the per person availability of calories will fall 4% of what's recommended by 2100. Most major staple crops, including rice, wheat, sorghum, maize, and soybean, will see diminished yields by 2050 as well as 2100. Wheat yield in northern India could be severely affected whereas rice yield in India less so. These findings are part of a modelling study assessing the impact of rising temperatures on global food production. While such studies are a dime a dozen, this specific study, appearing in Nature, is unique in that it accounts for producer adaptation. This means being able to fit into a mathematical model how farmers and those connected with agriculture around the world implement measures to adapt to rising temperature, such as by choosing heat-resistant varieties, altering the timing of sowing, and tweaking the times the crops are watered. Accounting for such practices, the authors say, offers a more 'realistic' picture of the impact of warming on crop yield. This mode of analysis, the authors claim, is an improvement over the bulk of existing, comparable econometric analysis. In such studies, projections of productivity are based on outputs from 'experimental farms' where conditions are tightly controlled and the researchers impose 'adaptation rules'. Such studies have usually projected productivity gains by 2100 of 1.3% for maize, 9.9% for wheat, 15.3% for soybean, and 23.3% for rice. For their analysis, the researchers relied on what they say was one of the 'largest datasets' of subnational crop production available containing 13,500 political units, covering 12,658 subnational administrative units from 54 countries for six staple crops spanning diverse local climates and socioeconomic contexts. Warming can affect yield by exposing plants to adverse temperature or by altering precipitation, which then affects the optimal moisture available for rice and wheat to properly flower. Assuming agriculturists globally responded optimally to the changing climate with the appropriate interventions, 23% of global losses could be alleviated in 2050 and 34% at the end of the century but 'substantial residual losses' would remain for all staples except rice, the authors note. While similar analyses project the greatest damages to the global poor, the new study suggests global impacts are dominated by losses to 'modern-day breadbaskets with favourable climates and limited present adaptation,' although losses in low-income regions were also 'substantial.' Thus, innovation, cropland expansion or further adaptation may be required to ensure food security, they note. Wheat losses are notably consistent across the main wheat-growing regions, with high-emissions yield losses of -15% to -25% in Eastern Europe, Western Europe, Africa and South America and -30% to -40% in China, Russia, the US, and Canada. There are notable exceptions to these global patterns: 'wheat-growing regions of Western China exhibit both gains and losses, whereas wheat-growing regions of Northern India exhibited some of the most severe projected losses across the globe,' the study found. High-emissions rice yield impacts were 'mixed' in India and Southeast Asia, which lead global rice production, with small gains and losses throughout these regions. This regional result was broadly consistent with the work of similar studies. In the remaining rice-growing regions, central estimates are generally negative, with magnitudes in Sub-Saharan Africa, Europe and Central Asia exceeding -50%, the study notes.

NDTV

3 days ago

• NDTV

Casino Lighting May Be Secretly Pushing You To Gamble More, Reveals Study

A new study by researchers from Flinders University and Monash University in Australia suggests that casino lighting may play a surprising role in encouraging risky gambling behaviour. The research found that blue-enriched lighting, commonly used in casino decor and LED screens, may influence brain responses, making individuals less sensitive to financial losses. The study published in Nature's Scientific Reports journal examined participants' economic decisions using a series of casino scenarios under blue-enriched and blue-depleted light to assess the impact of light wavelengths on risk preferences. "We found that light with more blue wavelengths in it, which is frequently emitted by LED screens and casino lighting, could subtly influence how people perceive losses and gains," says lead author, Dr Alicia Lander from FHMRI Sleep Health. "This raises questions about the role of lighting in environments like casinos or online gambling platforms." According to the news release by Flinders University, the study investigated whether circadian photoreception affects risk-taking behaviour during gambling by manipulating the 'melanopic' brightness of light, which targets the body's internal clock, while keeping visual brightness constant. The results showed that participants exposed to blue-enriched light became less sensitive to losses, making them more likely to choose risky financial options over safer alternatives. "Typically, people have a strong tendency to avoid losses, often outweighing potential gains in their decision-making," says Dr Lander. "However, under blue-enriched light, which stimulates non-visual circadian photoreceptors, they demonstrated a reduced sensitivity to financial losses that may influence gambling tendencies, potentially encouraging riskier behaviours. "Under conditions where the lighting emitted less blue, people tended to feel a $100 loss much more strongly than a $100 gain - the loss just feels worse. "But under bright, blue-heavy light such as that seen in casino machines, the $100 loss didn't appear to feel as bad, so people were more willing to take the risk." The study suggests that blue light alters neural processing in brain regions tied to reward and decision-making, such as the amygdala and habenula, possibly dampening negative emotions associated with losses. "Interestingly, we found that women displayed greater loss aversion than men, showing more reluctance to take risks under both light conditions," says Dr Lander. "This aligns with previous research indicating that women often experience stronger emotional responses to financial uncertainty, while men may have a greater tolerance for risk."

Time of India

4 days ago

• Time of India

Homo Sapiens Adaptability: Early humans survived in a range of extreme environments before global migration, study says

WASHINGTON: Humans are the only animal that lives in virtually every possible environment, from rainforests to deserts to tundra. This adaptability is a skill that long predates the modern age. Tired of too many ads? go ad free now According to a new study published Wednesday in Nature, ancient Homo sapiens developed the flexibility to survive by finding food and other resources in a wide variety of difficult habitats before they dispersed from Africa about 50,000 years ago. "Our superpower is that we are ecosystem generalists," said Eleanor Scerri, an evolutionary archaeologist at the Max Planck Institute of Geoanthropology in Jena, Germany. Our species first evolved in Africa around 300,000 years ago. While prior fossil finds show some groups made early forays outside the continent, lasting human settlements in other parts of the world didn't happen until a series of migrations around 50,000 years ago. "What was different about the circumstances of the migrations that succeeded - why were humans ready this time?" said study co-author Emily Hallett, an archaeologist at Loyola University Chicago. Earlier theories held that Stone Age humans might have made a single important technological advance or developed a new way of sharing information, but researchers haven't found evidence to back that up. This study took a different approach by looking at the trait of flexibility itself. The scientists assembled a database of archaeological sites showing human presence across Africa from 120,000 to 14,000 years ago. Tired of too many ads? go ad free now For each site, researchers modelled what the local climate would have been like during the time periods that ancient humans lived there. "There was a really sharp change in the range of habitats that humans were using starting around 70,000 years ago," Hallet said. "We saw a really clear signal that humans were living in more challenging and more extreme environments ." While humans had long survived in savannas and forests, they shifted into everything from dense rainforests to arid deserts in the period leading up to 50,000 years ago, developing what Hallet called an " ecological flexibility that let them succeed." While this leap in abilities is impressive, it's important not to assume that only Homo sapiens did it, said University of Bordeaux archaeologist William Banks, who was not involved in the research. Other groups of early human ancestors also left Africa and established long-term settlements elsewhere, including those that evolved into Europe's Neanderthals, he said. The new research helps explain why humans were ready to expand across the world way back when, he said, but it doesn't answer the lasting question of why only our species remains today.