Microbiota - Undernutrition and weight loss

The term malnutrition refers to deficiencies, excesses or imbalances in a person intake or nutrients and energy and addresses to three groups of conditions:

1. Undernutrition
2. Micronutrient related malnutrition
3. Overweight.

1. Undernutrition - If you don't have enough nutrients, you are malnourished. It is not always the lack of food, but the lack of quality food. Undernutrition means that you have a shortage of calories and most often of essential nutrients (when the access to food is denied). This is a specific type of malnourishment. As a result, you are being underweight, wasted, growth  is stunted, happening usually after a weight loss event such as infectious disease associated with diarrhea. Stunting means that a person has a low height for age, and it is the result of a long term undernutrition during childhood, holding the child back from achieving their physical and intellectual potential. being underweight is a child with a low weight for age, and you can also be stunted or wasted.

There are clear differences in the gut of the undernourished people compared with healthy individuals. Most of the researches on undernutrition are focused on children, because they need fast growth for their optimal development. Undernutrition in children can have long term health implications: reduced growth rate, immune and cognitive development.

In the same time, the gut microbiota of the undernourished children remains immature. But we do not know if this is a cause or a consequence. In a mice study, after transferring the gut microbiota of a malnourished infant donor, the mice will gain less weight than the ones receiving microbiota from a healthy donor. Undernourished infants often miss bacteria from Ruminococcus and Clostridium group. All those bacteria are the ones producing the short chain fatty acid called butyrate (which is an energy source for the host cells). The microbiota can contribute to the caloric value of your food. This is useful especially when food is scarce, and any part is needed as usable energy.

Ruminococcus bacteria

Another type of malnutrition is Anorexia Nervosa (which is characterized by distorted body image, extreme dieting and the anxiety of becoming obese as main underlying factors). All these symptoms will lead to severe weight loss. Even if it seems different that the undernourishment in children, the common element is the nutrient shortage. And similar changes are noticed in the composition of the microbiota. Anorexia patients will have lower amounts of total bacteria and obligate anaerobic bacteria. In addition, they will also have lower amounts of butyrate producing bacteria and higher amounts of mucin degrading bacteria.

The undernutrition is affecting the microbiota and plays a role in the severity of the undernutrition by releasing less energy from food. The manipulation of the gut microbiota could be a helpful solution for undernourished children.

Next post: Microbial therapies and diagnostics

Microbiota and obesity

Our gut bacteria can be partially blamed for being overweight or obese. There is a causal link between the microbiota and obesity, driven in combination with overnutrition and drastic lifestyle changes.

The prevalence of obesity is reported to increase worldwide and it is a major challenge in our modern days. There are various attempts to explain the large increase in obesity, mostly due to the last three decades of research. They include calorie intake, changes in dietary composition, decrease in physical activity and changes in the gut microbiome. Is the gut microbiota contributing to the excessive weight accumulation in our body? A piece of evidence was published in 2005, when scientist found that obese mice microbiota composition is different from the healthy lean ones. An increase of Phylum Firmicutes bacteria was noticed in the obese mices, and their microbial diversity was lower than normal. This made them wonder if is obesity causing the changes in the microbiota or is the gut bacteria causing obesity? They got sample from human twins (one fat, one lean) and give them to germ free mice. The ones with bacteria from the slim ones stayed slim, the others quickly gained weight. So the conclusion was that there is a direct causal link between the gut microbiota and the weight gain. The next trials started with gut microbes from lean humans, given to obese individuals, and they improved their metabolic response and experienced weight loss. The effect lasted for few weeks when the study was done, but we do not know if the effect is sustained. Also, fecal transplant is prone to high risk of infection. We will talk later about this.

The gut microbiota is a major contributor to obesity. Our diet is another one, as the Western style diet is an example , characterized by highly processed and refined foods, rich in proteins and fats. It has a high salt, fat and sugar content, with protein mainly from red meat. This diet is the major contributor to the actual crysis of obesity and to a wide range of obesity related diseases. This type of diet leads to a low presence of bacteroidetes and akkermansia, followed by an increase in the firmicutes and proteobacteria groups. These alterations were associated with obesity and the subsecvent related chronic diseases. The high fat content causes an overload in energy leading to obesity, but the change in microbiota can also cause inflammation, which in turn can lead to many obesity related diseases.

Diet can increase obesity and obesity related diseases directly and indirectly. The evidence supporting the link between obesity and lifestyle changes is very strong. Modulation of the microbiota might help to ameliorate metabolic responses and initial weight loss attempts. Adapting the microbiota might be useful to keep a healthy weight or even to lose weight.

Next post: Undernutrition and weight loss.

See you soon.
G.

Microbiota - Man versus mice

There are clear differences between the genomes and diets of different species. Is there some evolutionary relationship of animal microbiota? There is indeed a definite difference between the genomes and diets of different animal species. Choosing the microbiome of the elephant, panda, python and few others for study, the microbiota of different animals will form clusters based of their evolutionary distance and dietary behaviour. We got herbivores, carnivores and omnivores. If we look for similarities based on the types of microbes and their abundance in the gut, then animals who are evolutionary close are also more alike on the microbiome level. But even for a big group like herbivores, there are clusters, based on whether the animal is a foregut or hindgut fermenter. Let me explain. A foregut fermenter has a fermenting chamber called rumen placed before the stomach. A hindgut fermenter has a fermenting chamber called cecum at the end of small intestine. Because they are different evolved digestive organs, they are selective for different microbes, hence the difference in the microbiota. The microbes are different based on the evolutionary relatedness of the host, but this clear separation dissapear when we consider the microbiota gene content. The gut microbial communities all share genes with similar functions, so even if the microbes are different, the functions executed are similar.

There was an experiment done, where zebra microbiota was transplanted to germ free mices. The microbes had to find a previous balance in their overall structure, adapting to the new host in the same time. The new environment forces the macrobiota to reach a new stable state. The new environmental conditions are determined by host genetics and lead to specific immune system and physiology, but they are also determined by the host dietary habits. There was another experiment where microbes where transferred from mices to germ free mice and from fish to germ free fish. The conclusion was that the host genetics is of major importance for the microbiota development. The mouse itself will adapt to the new microbiome using immune and metabolic adjustments.

So, the microbiome will adapt to its specific environment as the genetic make-up of the host and its dietary habits will determine the environmental conditions. Every animal species carry their own specific microbiota.

Next post : Microbiota and obesity. Now this will be an interesting one!

Notes (A blast from the past)

The man was looking mesmerized at the towering monster that just came out of the lake's calm waters, and for a moment froze. It was then when i turned and I could see him. Like every other human until now, stopped for a moment, looked at me and start to run back to his small village.

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Ship Journal Log 21365 - Year 5

The giant lizzards just got extinct when a big meteorite has fallen in the western hemisphere of the planet.

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Ship Journal Log 456365 - Year 61.333.215

I am kind of bored with this exploring mission. But the primates just started to use rudimentary tools. I am thinking to help them evolve a bit by teaching how to start a fire.

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Ship Journal Log 45578- Year 61.333.232

I like to think that i saved the future intelligent life on this planet. Just as i teach them how to make fire, another ice age just started. Most of the giant mammals got extinct.

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Ship Journal Log 1245365 - Year 65.245.235

My new favorite species started to paint the walls of their caves. I see a glorious future.

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Ship Journal Log 1294576 - Year 65.428.520

Humans are petty little creatures, thinking only at war and destruction. But there are few of them that make me hope that the end of the cycle will not come very soon. This Leonardo guy is bringing the art to a new level right now.

....

Ship Journal Log 1298254 - Year 65.429.005

Oh, they found the entrance of my underground base, but the shields are still on. I have a name now. Nessie, also known as the Lock Ness monster. How cute!

(This was the last entrance from our explorer from Solar System XFSTF 31337)

....



Press Release 15.12.1998 16:45 - After decades of terror and mysterious dissapearings, a serpent-like animal was killed by the Police helicopter near Lock Ness. We want to thanks to Mr. John Major, who promptly reported and confirmed the target location.

Microbiota - twins and siblings

Your genetic makeup is an important factor determining what your microbiota looks like. Let's explore the close relationship between diet and genes.

The example used is the one of two twins, whom are genetically identical. However, their microbiome is not identical, due to the different environmental factors that they were exposed. Twin number one doesn't like veggies, and twin number two is vegan. They also have a sister who can eat everything. She is genetically different that the twins, so if we compare the twins with her, their microbiome becomes very similar, but if we compare the sister microbiome with other people outside her family, all three of the siblings share more similarities. The reasons behind this observation lays within their genes and their shared environment. They are born by the same mother and they are often eating same food.

Looking even wider, they share common similarities with the whole human race, compared with the rest of the animals. The genetic background is a very important co-founder for microbiota's composition, influencing the elusive relationship between your own microbes and the diet. The way of how each host microbes evolved in case of humans is clearly distinct from that of other animals. Even the genetic differences between different human beings influences the microbiota composition.

In conclusion, the transmission of our microbiota and the establishment of a stable microbiota depends on environment, genetic information and diet (eating habits).

Next post: Microbiota - about mice and men

Stories from the upper-world, mutation and far-fetched dramas

We learn from this article that somewhere on this planet, there is a woman who did not experienced fear or anxiety, because of a rare gene mutation that made her immune to pain. The story documents the case of a woman, Jo Cameron, who doesn’t feel pain. She actually burns and cuts herself quite often because of this. Perhaps equally fascinating is that even though she cuts and burns herself frequently, the injuries rarely left scars, and her body heals quickly. Researchers attribute her pain-free existence and quick-healing abilities to a “microdeletion” in part of a gene called FAAH-OUT. (Interestingly, the endocannabinoid system is prominently involved.)

They are thinking that because she is living a pain free life, she almost never experienced anxiety or fear. But maybe is the reverse of the medal. we know that emotions bring changes into the body, physical changes, and maybe this is the reason. If your emotions do not translate in painful experiences, the fear dissapear. Just think about it and its implications.

And have a bright day!

G.

Looking up to the northern sky

Wow! I cannot believe that it was 7th of July when i put my last post. Yeah, i have plenty of excuses, more or less expensive. Laptop needed repair, then phone did not charge so i need to buy a new port for the phone. Nine night shifts, so i still need to recover from it, and even 3 days without internet, courtesy to Virgin Media.

I will try slowly slowly to get back to work, especially the online one.

See you soon.
G.

Microbiota - Community types

The human gut microbiota is different in all the humans being worldwide, so your microbiota is like your personal fingerprint. However, there are many similarities between different microbiota, and this information can be used by us to develop health biomarkers and to define therapeutic strategies.

The human gut consists in trillions of microbes and the whole ecosystem varies between individuals in diversity, distribution and abundance. In any ecosystem the selective pressures, disturbances and survival conditions are very important in defining the species leading to a distinct community type in that area. There was a study on human microbiome investigating the impact of possible steering factors such as the dietary habits. The observation underlines that certain combination of microbes, distribution and diversity can lead to a distinct community structure. But, even more important, the people can be grouped in 3 main groups, in a similar way to the blood group type. They can have a high number of Bacteroides, Prevotella or Ruminococcus. People eating a diet with less fibre and high in animal fat tend to have the Bacteroides community, people with a diet high in fibre and low in animal fat tend to have Prevotella community type and finally, was shown that every individual will have a gradient from high to low abundances on these three groups of bacteria. You can see that different dietary habits can support different microbes, and changes to diet can shift the percentage of each community type.

There is also the concept of the genes present in the microbial complex, which will define the potential of degrading complex fibres. So now the community type will also include this microbial gene into information. It turned out that some of us have high gene righness and others can have low gene richness. This low and high gene count can be used to separate individuals in a population. If you got inflammatory bowel disorder and obesity, you will usually have low gene richness. You are also more likely to get more weight than someone with high gene richness. All these concepts can be used to predict individual susceptibility to gain weight.

Even if the individual microbiota is different for each person, there are characteristics that are overlaping. Knowing how a community will respond to a diet and other pressures helps to develop health biomarkers and therapies.

Next post will be about twins and siblings microbiota.

Have a nice evening!
G.

Microbiota - dietary habits

As I promised, after i finished the Autism course, i will come back to the microbiota series.

Now, the course is finished, so we will talk today about dietary habits. We all know that our diet determine what our microbiota can feed off. So, knowing this, we can change our microbiota changing our diet.

How can we do that? Easy, but you need to learn about it. You want to lose weight, you will use a calorie deficit diet, and once you reached the desired weight, you stop. This move will have a drastic effect on your microbiota, but as soon as your eating habits are back to normal, your microbiota will regulate too, because it developed a stable state over the years, and that it is not easily disturbed.

I have read about an interesting study, where they switched the diets of a population of African-Americans with that of the rural Africans. The African-Americans were given a high fibre, low fat African style diet. The rural Africans were given high fat, low fibre Western style diet. After a while, the African style diet was shown to support beneficial microbes and improved function, the Western style diet increased the risk of cancer. This research shows how short dietary changes can affect our microbiome and health.

In order to understand the long term effects of dietary habits, the researchers studied a number of individuals from different countries. People from Western world with  a diet of high protein and low fibre content tend to have more Bacteroides bacteria. People from rural Africa tend to have more Prevotella bacteria. With all the advances regarding food, we are losing our ancestral microbiome due to changes in our dietary habits and surrounding environmental factors. This can have a negative effect on health, leading to diabetes development, colon cancer, I.B.D., all of them being more prevalent in the western world.

I hope you enjoyed this new introduction. Next post will be about community types.

See you soon.
G.

Future posts

I got many ideas on the future blog posts, but at the moment i am very busy trying to finish an Autism course quite quickly. After that i will come back to the microbiota articles, and then I wil follow with micronutrients. I have some ideas about rejuvenation, mind boosters, nootropics and treating senescence (anti-ageing strategies). But this is still ongoing.

I will give you some homework if you are curious by nature. Search about the 2 pathways activated by rapamycin, about liposomal glutathione levels decrease as we age , resveratrol, ginsengoids and how real are the pre-biotic products.

That's all for today.
Enjoy this beautiful summer.

G.

A real home

We are humans.
I just realised now, for a countless time, that I keep forgetting to listen to the voice of my soul. I became aware once more, and I am slowly reaching that deep level of peace and silence. I am back home. Where my real home is.

Welcome home, my friends! I wish you the same.

Macrobiota - mucus and milk fermentation

The food that you consume is the one feeding your microbiome. Everything that cannot be digested by yourself it is used by your microbiome, which will transform all these indigestible components into energy that it is used by you.

Some beneficial microbes nibble on you eating the mucus produced by your body, as the human body will produce around 10 liters of mucus every day. The mucus is made of a protein backbone with chains of sugar molecules attached to it, known as mucus glycans. Some microbes adapted to eat these glycan structures produced by our body. These microbes are specialized in the consumption of the host-produced glycans, such as in mucus. Another type of glycans produced by the human body are the human milk oligosaccharides. The glycans in mucus and human milk are structurally alike, they are awkward sugars, rarely found in plants. This is why not many microbes can degrade these glycans.

The dietary glycan starch is a sugar chain of only glucose molecules, while primary sugars of mucus and milk glycans are n-acetilglucosamine, fucose, manose and sialic acid. Because these can be used by the microbiota, they are considered pre-biotic substances to nurture specific microorganisms (who serve a beneficial and protective role for the most).

The group of bacteria specialized in the degradation of the human milk oligosaccharides are known as bifidobacteria. In early life , bifidobacteria plays a role in energy harvest for the infant, they also play a crucial role in the immune and metabolic imprinting. Later in life, permanent colonization of the mucosal layer also leads to immune and metabolic regulation contributing to the host health. Because many pathogens use mucus as a signal to attack, the beneficial mucus colonizing microbiota members will protect against such pathogens. The host tolerates microbes in the mucosal layer and even produce extra mucus when sensing their presence. Another reason of existence of awkward sugars is that, if all bacteria will degrade the mucosal layer, this could be problematic.

In conclusion, some microbiota members like eating the glycans from mucus and milk. Early life, they release energy from human milk, later in life they serve as a line of defense against pathogens. They also stimulate a healthy host immune and metabolic response. Our body will nurture specific members of the microbiota by producing special sugars.

Next post will be about long versus short dietary habits.

See you soon!
G.

Microbiota diet and disease

Probably everyone knows that our microbiota is an anaerobic chamber with trillions of bacteria which work together and their combined efforts help us break down food and harvest as much energy as possible from the food we eat. Our microbiota depends a lot on the food we consume. In return, it will help us to digest the food we consume. Without the bacteria from our gut, the nutritional value of our food would be a lot lower (we would probably eat 5 times as much food to reach the same energy levels).

When microbes start to degrade the fibers from our food, this process is called fermentation. Microbial fermentation is a common process used to produce food (cheese, beer, bread etc.). All these foods have microorganisms added to them during the making process, leading to special taste or alcohol. Our microbiota also carries out a wide range of fermentation processes, using anaerobic fermentation in order to sustain the inner environment. The bacteria ca ferment both sugar and protein from our food, leading to the production of many chemicals with energetic value, essential vitamins and health stimulating products that are released in our guts by the microbiota. Many compounds are short chain fatty acids such as lactic acid, acetate, butyrate and propionate. All these short chain fatty acids are a major source of energy for our intestinal cells. Almost 10% of the energy used by our intestinal cells comes from the microbial produced butyrate. The butyrate and the propionate have several health benefits (pain reduction and inflammation response reduction).

The microbiota is actually a microbial ecologic network, so, for optimal functionality, we need to have a microbial diverse microbiota. Our gut is an anaerobic chamber with trillions of bacteria working together and their combined effort helps us to break down food and to harvest as much energy as possible from the food we eat.

I will post next about mucus and milk fermentation.
See you soon!
G.

Microbiota cycle - reloaded

I have a new series of articles about the microbiota, all of them fascinating from some point of view. i will start soon with  microbiota diet and disease.

See you soon
G.

Macrobiota and immune system ageing

There is a difference between intestinal flora composition of elderly in the community, compared with the elderly in long term care. In this case, we will have four groups of subjects, to compare. We have the first group case, elderly living in a local community, in their homes, second group, elderly attending out-patient day hospitals, third group, elderly in a short term hospital care, and the last group, long term residential care elderly.

There are clear differences between them, with residential care group having a higher proportion of Bacteriodetes,and the community group having a higher proportion of Firmicutes. We have Parabacteriodes, Eubacteria and Copprobacillus associated with elderly in residential care. Elderly living in the community had a more diverse microbiota, more abundant in bacteria like Copprococcus and Roseburia.

In conclusion, the elderly benefit more from staying in their own homes, possibly because of their exposure to a bigger variety of foods and environmental factors. The knowledge gained from these researches can be used to stimulate the missing healthy bacteria and to improve microbiota diversity and the health of the elderly in residential care.