Probiotics Could Control "Inflammaging"

04/19/2015 11:33 EDT | Updated 06/19/2015 05:59 EDT
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No one wants to grow old but time is always against us. The outward signs of aging are bad enough, but what happens on the inside is even more frustrating. As the years pass by, a number of changes happen including a weakened immune system and the onset of what is known as inflammaging. This phenomenon can contribute to a number of chronic diseases including arthritis, osteoporosis, cardiovascular troubles, cancer, and even Alzheimer's disease.

The trouble with inflammaging is how hard it can be to detect. It's a long-term condition in which the entire immune system is working at a heightened level to get rid of any potential threats to health. For younger people, this is actually a good thing; the response to infections and other toxins is faster and leads to a more efficient recovery. But in the elderly, the opposite effect happens. The immune system can turn on a person and begin to harm the very cells needed for life. The overall effect is a greater risk for disease as the damage accumulates.

Detecting the condition may be hard but figuring out how to control the problem appears to be an even greater puzzle. Reducing inflammation is not easy and isn't going to be resolved simply by taking pharmaceutical anti-inflammatory medications. A more systemic answer needs to be found although the options are limited.

One of the more popular directions in controlling inflammation involves targeting not human cells but microbial ones. The trillions of bacteria in the intestines are known to play a role in inflammation particularly in the elderly. The key to optimal health is a strong diversity of species yet as people age the variety tends to drop. In people over seventy-five, the effects are more pronounced. If a person makes it to 100, the number of bacteria working to control inflammation is quite lower. This leads to a higher risk for inflammaging and the resulting consequences.

When it comes to solving issues with gut diversity, one proposed option for resolution is probiotics. This class of bacteria is known to provide a host of benefits including controlling inflammation. The means by which this happens is through the production of a number of molecules known as short-chain fatty acids. One of them, butyrate, appears to have a universal effect on inflammation, helping to keep the entire immune system balanced. In the elderly, this molecule appears to be reduced and may play a role in inflammaging. To combat this, the addition of probiotics to increase butyrate levels appears to be a viable option.

Last week, an American team of researchers decided to test whether probiotics can help control the problem of inflammaging. They used one particular probiotic species, Lactobacillus rhamnosus GG, and tested whether this bacterium alone could help to reduce inflammation and improve elderly health. What they found offered hope for a possible natural treatment in the future.

The team recruited 12 individuals between the ages of 65 and 80 and provided them with two daily doses of 10 billion bacteria for 28 days. Fecal samples were taken from the individuals at day zero, and also at days 28 and 56, representing four weeks after the probiotic supplementation was stopped. The samples were then processed to identify the bacteria contained within and the various activities conducted by the population. Some of these processes are known to have an effect on human systems, particularly immunity. As a result, the group could look for any potential links to inflammaging.

What they found was fascinating. The actual diversity of the species didn't change in a uniform manner. The populations did not shift significantly in one way or another and each individual continued to have similar microbial profiles. This suggested L. rhamnosus did not play a role in deciding which bacteria stayed and which ones had to go. But when the focus changed from the nature of the bacteria to what they did, a different story emerged.

At the metabolic level, addition of the probiotic led to an increase in the activity of a number of different species known to produce butyrate. Some of these bacteria also aid in the absorption of the short-chain fatty acid by the intestines. Although the team did not look at the immune status of the individuals, the increased levels of butyrate during the intervention suggested there may be an anti-inflammatory effect.

There was one further observation made by the team. At day 56, a month after the probiotic treatment was over, the benefits were essentially gone. The gut microbiota had returned to its original state. The results showed the effects of the bacterium were short-lived and required continued supplementation to keep them going. This result challenges some suggestions probiotics can change the diversity of the gut bacteria. While a lasting change in the gut microbiota has been seen in the elderly previously, no such modification was seen in this study.

The results of the study suggest there may be a natural way to treat inflammaging using continued supplementation of probiotics. Although the authors only tested 12 people, the study opens the door to larger clinical trials and possibly even longer times for L. rhamnosus administration. The observations also reveal why probiotics need to be taken regularly. Many are transient and only offer benefit for a short period of time. When they are present, life is good but when they make an exit, everything returns to way it was, regardless of how bad it may be.


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