Tag: taurine

Categories : GastrointestinalTags : Leave a comment

Silent but Violent: Taurine-consuming Bacteria Protects the Gut with Toxic Gas

On By ModernMedia
Photo by Pablo Stanic on Unsplash

Researchers have discovered a new intestinal bacterim that feeds exclusively on taurine and produces the foul-smelling gas hydrogen sulfide. The results, currently published in Nature Communications, show that Taurinivorans muris protects against Klebsiella and Salmonella, two important pathogens.

Chemical warfare in the gut

One of the ways the gut microbiome helps regulated health is in contributing to the levels of hydrogen sulfide – the toxic gas responsible for foul-smelling farts. Having small amounts of hydrogen sulfide in the gut is a good thing; in fact, it’s essential for a number of physiological processes, and can even protect against pathogens. Hydrogen sulfide-producing microbes in the gut may help “choke out” oxygen-dependent pathogens such as Klebsiella, making it harder for them to colonise. However, excessive levels can have negative consequences and have been associated with gut inflammation and damage to the intestinal lining.

Taurine plays yet another a role

The bacterium Bilophila wadsworthia is one of the most important taurine utilizers in humans. In the current study, researchers led by Alexander Loy at CeMESS, the Centre for Microbiology and Environmental Systems Science of the University of Vienna, have discovered a new genus of hydrogen sulfide-producing bacteria in the mouse intestine. “The bacterium we described has a rather unbalanced diet,” explains Loy, “it specialises in consuming taurine.” Taurine is a semi-essential amino acid, synthesised in small amounts in the liver but mostly obtained through the diet – especially meat, dairy and seafood. 

Like hydrogen sulfide, taurine is implicated in a plethora of physiological processes. Recent studies have found a link between taurine and healthy ageing – it seems this nutrient may stave away age-related disease. In light of these findings, the discovery of a new gut microbe that feeds exclusively on taurine (aptly named Taurinivorans muris) is another piece of an exciting puzzle. “By isolating the first taurine degrader in the mouse gut, we’re one step closer to understanding how these gut microbes mediate animal and human health” explains Huimin Ye, lead author of the study. 

To access sufficient taurine in the gut, however, Taurinivorans muris needs the help of other gut microbes to release it from bile acids. Taurine-containing bile acids are produced in the liver and are increasingly released into the intestine during a high-fat diet to help our body digest fats. The activities of the bacteria in the intestine in turn influence the bile acid metabolism in the liver. The results of the Viennese researchers therefore also contribute to a better understanding of these complex interactions in bile acid metabolism, which has an impact on processes and diseases throughout the body.

Taurine-degrading microbes choke out pathogens

One of the most important functions of the symbiotic microbes in the gut is to defend against pathogens. The microbiome has a versatile arsenal of protective mechanisms – and utilising taurine to create hydrogen sulfide is one of them. “Hydrogen sulfide may suppress the oxygen-dependent metabolism of some pathogens,” explains Ye. In the present study, the researchers found that Taurinivorans muris has a protective role against Klebsiella and Salmonella, two important gut pathogens. “The protective mechanism of Taurinivorans muris against pathogens may be via hydrogen sulfide but is essentially not yet fully understood” adds Alexander Loy. Taurine is one of the most important sources of hydrogen sulfide production in the gut. The study thus generates basic knowledge on the physiological interactions between the different gut microbes and their hosts, which is necessary to develop new microbiome-based therapies.

Source: EurekAlert!

Categories : Ageing Diet and NutritionTags : Leave a comment

Taurine may Help Extend Healthy Lifespan

On By ModernMedia
Photo by Barbara Olsen on Pexels

A deficiency of the amino acid taurine is a driver of ageing in animals, according to a new study published in Science. The same study also found that taurine supplements can slow down the ageing process in worms, mice, and monkeys and can even extend the healthy lifespans of middle-aged mice by up to 12%.

“For the last 25 years, scientists have been trying to find factors that not only let us live longer, but also increase healthspan, the time we remain healthy in our old age,” says study leader Vijay Yadav, PhD, assistant professor of genetics & development at Columbia University. “This study suggests that taurine could be an elixir of life within us that helps us live longer and healthier lives.”

Anti-ageing molecules within us

Many studies into ageing have found that various molecules carried through the bloodstream are associated with ageing. Less certain is whether these molecules actively direct the ageing process or are just passengers going along for the ride. If a molecule is a driver of ageing, then restoring its youthful levels would delay ageing and increase healthspan, the years we spend in good health.

Taurine first came into Yadav’s view during his previous research into osteoporosis that uncovered taurine’s role in building bone. Around the same time, other researchers were finding that taurine levels correlated with immune function, obesity, and nervous system functions.

“We realised that if taurine is regulating all these processes that decline with age, maybe taurine levels in the bloodstream affect overall health and lifespan,” Yadav says.

Taurine declines with age, supplementation increases lifespan in mice

First, Yadav’s team looked at levels of taurine in the bloodstream of mice, monkeys, and people and found that the taurine abundance decreases substantially with age. In people, taurine levels in 60-year-old individuals were only about one-third of those found in 5-year-olds.

“That’s when we started to ask if taurine deficiency is a driver of the ageing process, and we set up a large experiment with mice,” Yadav says.

The researchers started with close to 250 14-month-old female and male mice (about 45 years old in people terms). Every day, the researcher fed half of them a bolus of taurine or a control solution. At the end of the experiment, Yadav and his team found that taurine increased average lifespan by 12% in female mice and 10% in males. For the mice, that meant three to four extra months, equivalent to about seven or eight human years.

Taurine supplements in middle age improves health in old age

To learn how taurine impacted health, Yadav brought in other ageing researchers who investigated the effect of taurine supplementation on the health and lifespan in several species.

These experts measured various health parameters in mice and found that at age 2 (60 in human years), animals supplemented with taurine for one year were healthier in almost every way than their untreated counterparts.

The researchers found that taurine suppressed age-associated weight gain in female mice (even in “menopausal” mice), increased energy expenditure, increased bone mass, improved muscle endurance and strength, reduced depression-like and anxious behaviours, reduced insulin resistance, and promoted a younger-looking immune system, among other benefits.

“Not only did we find that the animals lived longer, we also found that they’re living healthier lives,” Yadav says.

At a cellular level, taurine improved many functions that usually decline with age: The supplement decreased the number of “zombie cells” (old cells that should die but instead linger and release harmful substances), increased survival after telomerase deficiency, increased the number of stem cells present in some tissues (which can help tissues heal after injury), improved the performance of mitochondria, reduced DNA damage, and improved the cells’ ability to sense nutrients.

Similar health effects of taurine supplements were seen in middle-aged rhesus monkeys, which were given daily taurine supplements for six months. Taurine prevented weight gain, reduced fasting blood glucose and markers of liver damage, increased bone density in the spine and legs, and improved the health of their immune systems.

Randomised clinical trial needed

The researchers do not know yet if taurine supplements will improve health or increase longevity in humans, but two experiments they conducted suggest taurine has potential.

In the first, Yadav and his team looked at the relationship between taurine levels and approximately 50 health parameters in 12 000 European adults aged 60 and over. Overall, people with higher taurine levels were healthier, with fewer cases of type 2 diabetes, lower obesity levels, reduced hypertension, and lower levels of inflammation. “These are associations, which do not establish causation,” Yadav says, “but the results are consistent with the possibility that taurine deficiency contributes to human ageing.”

The second study tested if taurine levels would respond to an intervention known to improve health: exercise. The researchers measured taurine levels before and after a variety of male athletes and sedentary individuals finished a strenuous cycling workout and found a significant increase in taurine among all groups of athletes (sprinters, endurance runners, and natural bodybuilders) and sedentary individuals.

“No matter the individual, all had increased taurine levels after exercise, which suggests that some of the health benefits of exercise may come from an increase in taurine,” Yadav says.

Only a randomized clinical trial in people will determine if taurine truly has health benefits, Yadav adds. Taurine trials are currently underway for obesity, but none are designed to measure a wide range of health parameters.

Other potential anti-ageing drugs – including metformin, rapamycin, and NAD analogues – are being considered for testing in clinical trials.

“I think taurine should also be considered,” Yadav says. “And it has some advantages: Taurine is naturally produced in our bodies, it can be obtained naturally in the diet, it has no known toxic effects (although it’s rarely used in concentrations used ), and it can be boosted by exercise.

“Taurine abundance goes down with age, so restoring taurine to a youthful level in old age may be a promising anti-ageing strategy.”

Source: Columbia University Irving Medical Center