Gut Microbiomes

The relationship between the human gut microbiome to health and disease is strong. Human physiology, metabolism, nutrition, and immune function are all affected by the composition of the gut. If the composition of the gut microbiome is altered in a way that any of these functions are negatively affected, this can lead to disease. The developments of the microbiome, its complexity, and its functionality in health and disease have been extensively studied. In addition, the way in which it is altered has many implications in the cause of diseases, such as bowel disease, obesity, diabetes and cancer.

There are approximately 3.3 million genes (according to the European’s census of microbial genes) in the human digestive system. In comparison, it is about 150 times the count of 20,000-25,000 genes our own gene.

There are major effects in the United States and Europe to help identify the role of microbial communities in the human body. The colon requires a balance of microbial agents that assist with various functions of the body. An imbalance can lead to C.diff., irritable bowel disease (IBD), irritable bowel syndrome (IBS), neurological disorders, and obesity just to list a few. Many of these problems have grown to an epidemic proportion. Both the United States and Europe have started projects aimed at the microbial communities of the body and their roles in our health.

The hindgut is not only a fermentation vat, but it also stimulates immune responses, protects against pathogens, production and neutralization of toxins, and gene expression in host epithelial tissues (Milinovich et al., 2010). The cecal microbiome is extremely sensitive and can be affected by factors like gastrointestinal disease and dietary changes, which can lead to systemic consequences and even death (Costa et al., 2012). Therefore, healthy and balanced microbiota is vital for the overall wellbeing of the animal. By understanding external factors and how they affect the gut microbiota, this could help in diagnosing medical conditions and provide better treatment and prognosis of gastrointestinal diseases resulting in

The use of the first form of microbe-based therapeutics, probiotics, is beneficial for preventing disease. These live microorganisms are known to strengthen the equilibrium of the gut flora by the development of healthy gut

Species composition of bacteria in the gut is highly personalised and mostly determined by environment and diet. The proportion of each species changes throughout life and the elderly have a significantly different microbiome. The introduction of antibiotics through the course of life alters the variation and presence of bacteria via elimination, altering the species richness and evenness of the microbiome.

The gut microbiota encompasses trillions of microorganisms that inhabit the gastrointestinal tract (Carding et al. 2015). The composition of the gut microbiota is constantly evolving and can be susceptible to both endogenous and exogenous modifications (Carding et al. 2015). The microbiota

Over two-thirds of adults, or nearly 69 percent are considered overweight or obese. Of those, more than one-third are considered to be obese, while more than 1 in 20 are classified with extreme obesity.1 The main causes of these overwhelming rates of overweight and obesity are all too familiar: an unhealthy diet, a sedentary lifestyle and to a lesser extent perhaps genes play a role as well. In recent years, however, researchers have become increasingly focused on a potential additional contributor to the obesity epidemic that lives inside us all: billions and billions of gut microbes or microbiota.2

Bacteria, fungi, viruses and other organisms that make up the digestive system of our body actually outnumber the quantity of our cells. Over time research has made clear that these small organisms play a very important role in our health - both physically and mentally. All these microbes that inhabit our body are called microbiome, and they are estimated to weigh between two to six pounds. Most of these microbes live in our gut and intestines and they help us digest food, incorporate vitamins, and fight infections. Recent studies have revealed that bacteria in our digestive system not only affect our physical health, but it also plays a major role in our mental health. Gut microbiome has been linked to a range of complex behaviors, such

A number of studies, predominantly conducted in mice, have established a link between gut microbiota and obesity and have documented that a change in gut bacteria can have an effect on body weight. A 2004 study by Bäckhed et al. study was one of the earliest studies done on this topic and provided some of the first evidence that gut microbiota may play a role in energy balance and subsequently obesity.6 Conventionally raised mice were fed a polysaccharide rich diet and gained 40% more weight than germ-free mice fed the same diet.6 When gut bacteria from the conventionally raised mice was transplanted into the germ-free mice, the germ-free mice experienced a 60% weight gain in 2 weeks despite reduced food intake.6 Researchers attribute the weight

Scientists are beginning to recognize the link between gut microbiota and inflammation and the role it plays in the pathogenesis of obesity-related disorders like diabetes (type two). Using animals, scientists have been able to link obesity models of a microbiota composition that is different than what is expected when observed for obesity development and insulin resistance. This means that this altered microbiota composition is linked to the development of obesity and insulin resistance. This can be seen through multiple mechanisms, including “increased energy harvest from the diet, altered fatty acid metabolism and composition in adipose tissue and liver, modulation of the gut peptide YY and glucagon-like peptide (GLP)-1 secretion, activation of the lipopolysaccharide toll-like receptor-4 axis, and modulation of the intestinal barrier integrity by GLP-2”. It is imperative to understand the mechanisms that regulate gut microbiota compositions that produce these various compositions. During infancy, several factors that can affect the gut microbiota include delivery mode, type of feeding, hospitalization, and possible prematurity. The use of antibiotics and the infant’s diet are also becoming increasingly recognized as factors that can affect one’s susceptibility to developing type two diabetes. The typical Western diet has played a significant role in

It is surely not uncommon to see people carry around different kinds of disinfectant sprays and other chemical products in order to reduce the amount of bacteria and germs on their skin and in their body. However, the fact is that distal human intestine represents “an anaerobic bioreactor programmed with an enormous population of bacteria.” The study was conducted in order to assess the influence of microbiota on the energy storage in mice raised without exposure to any microorganisms compared to the control group that had acquired a microbiota since birth. The study showed that the control group of mice acquired 40% more total body fat than their germ free counterparts, despite the fact that the control group consumed less food per day. This came as a result of microbiota that provide us with genetic and metabolic attributes we have not acquired in our own evolutionary process, such as the ability to harvest otherwise inaccessible nutrients. Coming back to Elizabeth Willson’s contention, study of the microstructure, in this case the gut microbiota, has had a reorganizing effect on how we view our bodies and forced us put greater value to the role of microorganisms in our own survival.

The first article that was examined was “A Randomized, Double-Blind, Placebo-Controlled Trial: The Efficacy of Multispecies Probiotic Supplementation in Alleviating Symptoms of Irritable Bowl Syndome Associated with Constipation”. This article was written concerning a study that was done to examine the effectiveness of using probiotics to alleviate symptoms of irritable bowel syndrome (IBS). The main symptom that was being examined was constipation but bloating, abdominal pain, abdominal cramps, and flatulence were also looked at. Patients with IBS have been shown to have microbiota in their gastrointestinal tract that is much less stable than the microbiota in a healthy adult. This imbalance leads to problems in the digestive system including the symptoms that have been previously listed. Probiotics that are typically found in the digestive tract could be used to alleviate symptoms and restore balance. However, the correct probiotic must be chosen in order to be beneficial to the patient because probiotics are species and system specific.

Compared to our understanding of most microbiota living on and in humans, our understanding of our gut flora is relatively well developed. It is also an area where it is "common knowledge" that there are microorganisms

In his NPR article, “Finally, A Map of All the Microbes on Your Body”, science editor Rob Stein states several elementary facts about microbes: first, one in ten of the trillions of cells in the human body is actually “human”. Second, the body has a symbiotic relationship with these “non-human” cells. This beneficiary connection is seen in various microbial functions, such as battling infections and synthesizing compounds that are resistant to harmful infection. Stein describes a team of scientists who recently undertook the enormous project of mapping out the microbiome that is the human body, painstakingly cataloging the various microbes they encountered at different locations – as complicated as the map of an actual continent. The sheer