How Does Our Digestive System Function?

• The pancreas, gallbladder, liver, and gastrointestinal tract (GI tract) are just a few of the components that make up the digestive system. Both the big and small intestines are essential components of the GI tract. The gastrointestinal tract is a long, twisting tube that runs from the mouth to below the rectum. It is composed of hollow organs. The esophagus, mouth, stomach, small intestine, large intestine, and anus are the hollow organs that make up the GI tract. In addition, the gallbladder, pancreas, and liver are important digestive organs.

↳ The gut is known as the gastrointestinal tract

• The biliary system consists of the liver, pancreas, gallbladder, and bile ducts

• The digestive system is when the body takes in raw materials, and partially creating it into something it can use.
• Digestion creates glucose, which functions your brain and muscles. It also signals your body's messengers, like neurotransmitters and hormones.
• The gastrointestinal tract is somewhat of a factory that converts food into fuel, and your microbes are the workers. And what you get out of it is heavily influenced by the quality of your input.
• The small intestine has three parts: the duodenum comes first, followed by the jejunum in the middle, and the ileum at the end. In the large intestine, you have the appendix, cecum, colon, and rectum. The appendix is a pouch shaped like a finger that sticks out from the cecum, which is the first part of the large intestine. After the cecum comes the colon, and the rectum marks the end of the large intestine right above the anus.
• The movement of food through your GI tract is facilitated by a process known as peristalsis. The large, hollow organs in your GI tract are equipped with a muscular layer that allows their walls to move. This muscular activity propels food and liquids through the GI tract, ensuring thorough mixing within each organ. As food progresses, the muscle behind it contracts, pushing the food forward, while the muscle ahead of it relaxes to facilitate its movement.
• The food in our GI tract moves from:

↳ Mouth→Esophagus→Lower esophageal sphincter→Stomach→Small intestine→Large intestine→Rectum

How do Our Lungs Function?

• When you breathe in, air enters your lungs, and oxygen moves into your blood while carbon dioxide, a waste gas, moves from your blood to the lungs and is breathed out. This vital process is called gas exchange and is crucial for life. The lungs are the central component of your respiratory system, which also includes the trachea, chest wall and diaphragm, blood vessels, and other tissues. Together, these parts enable breathing and the exchange of gasses. Your brain regulates your breathing rate by sensing the body's need for oxygen and the removal of carbon dioxide.

↳Respiratory System

• Situated on either side of your heart within the chest cavity, your lungs serve as the primary organs of the respiratory system. The right lung is separated into three sections, while the left lung has two, slightly smaller due to the space occupied by the heart. During inhalation, air travels into your airways and reaches the air sacs, called alveoli, where gas exchange occurs.
• The airways are tubes that transport oxygen-rich air to the lung's alveoli, where oxygen is absorbed, and simultaneously remove waste gas, carbon dioxide, from the lungs. The airways include these body parts:
• Mouth 
• Nose (linked air passages called the nasal cavity and sinus)
• Larynx (voice box) 
• Trachea (windpipe) 
• Tubes called bronchial tubes, or bronchi, and their branches 
• Smaller tubes called bronchioles that branch off of the bronchial tubes

What is a Lung Microbiome?
Scientists using advanced methods that don't rely on specific cultural conditions have discovered that the lungs and airways contain a large number of microbes. Previous techniques couldn't detect this diverse microbial community. Research indicates significant differences in microbe types between healthy and diseased lungs. The lung microbiome, which includes these microbes, not only affects disease susceptibility but is also influenced by disease and treatment responses. Despite study limitations, exploring the lung microbiome can enhance our understanding of how the body and microbes interact. Furthermore, it's possible that using innovative multiple omics techniques to expand our knowledge of the lung microbiome can help us construct an indicator and diagnostic biomarkers for respiratory disorders in clinical settings.

What is a Gut Microbiota/ Microbiome?

• The gut microbiota is located in our large intestine. 

↳(The large intestine contains all the microbes that reside within the GI tract)

• These microbes are made up of bacteria, fungi, yeast, and viruses.
• When you eat, the stomach's gastric acid works to eliminate many of the harmful pathogens (organisms that cause diseases) present in the food.
• The gut microbiota plays a crucial role in digesting food in our bodies, metabolism, and inflammation. While you are an infant, your body is building up your gut immune system by using the gut microbiome. As an adult, the microbe helps maintain your immune system. 
• “Research is ongoing on how the gut microbiome works in tandem with parts of the body like your brain, heart, liver and lungs.” 

↳https://health.clevelandclinic.org/gut-microbiome

• The development of the microbiota is believed to begin from birth, it has also been studied and proven that the microbe can start developing in the womb.
• Gut microbes contain their own genes, which influence how your human genes function. Your body is composed of between 20,000 to 25,000 distinct human genes.
• Some studies involved transplanting healthy mice's microbiomes into stressed mice. Since, the stressed mice exhibited fewer anxiety symptoms.

How do Gut Microbiomes Benefit the Body?

• The microbiota activate the immune system, break down harmful food substances, and produce essential vitamins and amino acids, such as B vitamins and vitamin K. Notably, bacteria, rather than plants and animals, contain the crucial enzymes for synthesizing vitamin B12.
• Benefits of vitamin B12:

↳  -     Helps with red blood cell formation and anemia prevention

• Prevents major birth defects
• Supports bone health
• Helps body generate more energy

• Benefits of vitamin B:

↳  -     Activates enzymes that give energy

• Creating blood cells
• Preventing DNA damage
• Boosting cognitive performance

• Benefits of vitamin K:

↳  -     Supporting bone, cognitive, and heart health 

• Producing protein in the body
• Easing morning sickness
• Acts as an antioxidant
• Prevents/ slows down the risk of getting alzheimer's disease, osteoarthritis, and cancer

• Gut microbiota benefits in:

↳  -     Harvesting energy from digested food

• Protecting against pathogens
• Regulating immune function
• Strengthening biochemical barriers

Signs of an Unhealthy Gut Microbiome:

Most signs of an unhealthy gut microbiome are very common occurrences in individuals' daily lives. Such as:

• Constipation
• Diarrhea
• Bloating
• Fatigue
• Acid Reflux/ Heartburn

If an individual has gut dysbiosis (imbalance of microorganisms), common signs could include:

• Diabetes
• Obesity
• Inflammatory Bowel Disease (IBD)
• Irritable Bowel Syndrome (IBS)

 

What are the Disadvantages of Gut Microbiome?

Some disadvantages of gut microbiome are:

• Obesity
• Type 2 Diabetes
• Kidney Disease
• Heart Disease
• IBD & IBS
• Colon Cancer
• Anxiety
• Depression
• Autism
• Arthritis

The bacteria in your gut play a big role in how your body handles food. They influence important things like how many calories you get from what you eat and the nutrients you absorb. If there's an excess of these bacteria, they can turn fiber into fatty acids. This process might lead to the buildup of fat in your liver, causing a condition called "metabolic syndrome." This condition is often linked to type 2 diabetes, heart disease, and obesity. People with inflammatory bowel diseases like Crohn's disease and ulcerative colitis are thought to have lower levels of specific anti-inflammatory bacteria in their gut. The exact link between these conditions and gut bacteria is not fully understood, but it is believed that certain bacteria may trigger the body to mistakenly attack the intestines, potentially contributing to the development of these diseases. Anxiety, depression, and autism can be connected to the gut through a communication network called the "gut-brain axis," where nerve endings in the gut interact with the brain. Research has indicated a possible relationship between gut bacteria and disorders of the central nervous system, such as anxiety, depression, and autism spectrum disorder. In the case of arthritis, individuals with rheumatoid arthritis may have higher levels of bacteria associated with inflammation compared to those without the condition.

What is Gut-Lung Axis?

The gut-lung axis represents a two-way communication system between the gut and lungs, emphasizing their interconnected influence on overall health. Despite their distinct roles in digestion and respiration, research shows a complex relationship between them. Factors such as immune responses, gut microbiota, metabolites, neurological pathways, and inflammation contribute to this communication. This is particularly relevant in respiratory diseases like asthma, where disruptions in the gut can impact immune responses and worsen symptoms.

↳ Bacteria can reach your lungs through your mouth, from the air you breathe, and to your gut. So, both the environment and the bacteria in your gut can impact your respiratory health. Substances like short-chain fatty acids (SCFAs) travel to the lungs through the lymphatic system and blood. They play a role in lessening inflammation, fixing the gut lining, and defending against lung infections.

What is the Gut-Organ Axis?

The  gut-organ axis is a special network with every organ. The communication of these organs are composed of neural, endocrine, immune, humoral, and metabolic pathways. It is also important to note that all these different pathways are key regulators of the homeostasis or overall health of your body. Not only is it crucial that these pathways stay intact, but if they were altered it could lead to many diseases. The organs depend on each other, and in this review we found, instead of just all the organs working separately they work together, to keep you healthy. The overall health of the gut microbiome can affect all different aspects of the other organs health and even with a little unbalanced t could lead to a lot of problems. 

What is the Gut-Brain Axis?

Afferent spinal and efferent vagal nerve routes, as well as neuroimmune and neuroendocrine signals, are the pathways through which information is transmitted between the gut and the brain. Gut microbes have neurotransmitter-receptor sites which promote effective brain-gut communication.

What Are Some Foods That Help/ Repair the Gut Microbiomes?

Probiotic foods contain live microbiota, which are beneficial, and can also alter any individual's microbiome. These include fermented foods like kefir, yogurt with live active cultures, pickled vegetables, tempeh, kombucha tea, kimchi, miso, and sauerkraut. Also foods such as whole grains and beans could help repair an individual's microbiomes.

What Are Some Unhealthy or Bad Foods for the Gut?

• Foods containing antibiotics
• Animal Protein
• Fried foods
• Alcohol
• High-sugar foods
• Red meat

What are Probiotics?

Probiotics promote healthy digestion and immune system function by revitalizing your body's beneficial bacteria. Probiotics can also assist in the treatment or prevention of specific illnesses. They are particularly helpful for children who experience diarrhea or constipation, which are both typical, especially during the potty training phase. Probiotics may also help reduce some of the symptoms of inflammatory bowel disease and irritable bowel syndrome

How do Probiotics Affect Gut Microbiomes?

Probiotics compete with other intestinal microbes for receptors and binding sites on the intestinal mucosa, or could produce antimicrobial agents or metabolic chemicals that limit the growth of other microorganisms. Probiotics are generally thought to be dietary components that can affect the human gut microbiota and also regulate the makeup and structure of the intestinal flora.

How Does Gut Microbiome Develop in Infants/ Newborns?

Since infants and newborns do not develop essential bacteria in their gut at birth, they further develop microbiota from nursing from their mothers. Not only does the milk provide bacteria to the baby, but it specifically provides maternal bacteria, which is the first essential step to developing a microbiome for babies. The milk hosts over 200 species of bacteria such as the most common being streptococci,  staphylococci, and lactobacilli. These bacteria are the first step to development of a microbiome but what is the next? There are a specific type of bacteria that are called prebiotic oligosaccharides, these act like a fundamental glue that nourishes and promotes colonization of bacteria. It also helps the bacteria from not being digested or absorbed in the stomach acids.

What is Asthma?

Asthma is a persistent inflammatory airway disease, causing symptoms like wheezing, breathlessness, coughing, and chest tightness. Although genetics and environmental triggers are established factors in asthma, the gut microbiota has recently gained attention as an interesting player in this diverse scenario. Studies have shown that imbalances in the gut microbiota can have notable impacts, and disturbances in gut immune responses may play a role in the onset and advancement of asthma.

What is the Connection Between Gut Microbiota & Asthma?

Research on the gut-lung connection shows that the bacteria in your gut can affect how asthma develops and how severe it becomes. One important link is in how the immune system responds. The bacteria in your gut have a big role in shaping how your immune system grows and works. Changes in the types of bacteria in your gut, known as dysbiosis, have been connected to problems with the immune system and a higher chance of getting allergic conditions like asthma. Some types of bacteria in the gut have been seen in studies to help create regulatory T cells. These cells are crucial for keeping the immune system in balance and stopping too much inflammation. On the flip side, if there's an imbalance in the gut bacteria, it can make the immune system too active, increasing the risk of asthma and other allergies. Additionally, the bacteria in your gut produce substances called short-chain fatty acids (SCFAs) that have anti-inflammatory properties. These can affect how immune cells in the lungs work, influencing asthma.

Does Nicotine Have an Effect on the Gut Microbiome?

Inhaling nicotine changes the gut microbiota and decreases bacterial diversity in a way that is particular to a person's gender, which may add to the negative effects of nicotine on health in general. Nicotine may affect the colon's smooth muscles, which in turn affects gut motility and alters how quickly digested food passes through the gastrointestinal tract.

What are Some Chemicals In a Cigarette?

These are most of the chemicals found in tobacco and cigarettes:

• Acetone—found in nail polish remover
• Acetic acid—an ingredient in hair dye
• Ammonia—a common household cleaner
• Arsenic—used in rat poison
• Benzene—found in rubber cement and gasoline
• Butane—used in lighter fluid
• Cadmium—active component in battery acid
• Carbon monoxide—released in car exhaust fumes
• Formaldehyde—embalming fluid
• Hexamine—found in barbecue lighter fluid
• Lead—used in batteries
• Naphthalene—an ingredient in mothballs
• Methanol—a main component in rocket fuel
• Nicotine—used as an insecticide
• Tar—material for paving roads
• Toluene—used to manufacture paint

Analysis - 

The diagram shows the difference between a healthy gut microbiome and a dysbiotic microbiome in the gut. Specifically the diagram demonstrates the critical function that several gut chemicals, particularly butyrate, play in maintaining a positive gastrointestinal environment. Many aspects of health are impacted by these interactions, such as insulin sensitivity, metabolism, inflammation, and more. These interactions support general health in a balanced state, while imbalances (dysbiosis) can have negative consequences. Furthermore the bacteria shown are obligate anaerobic bacteria and pathogenic bacteria. The specific difference in these bacteria is that the obligate anaerobic bacteria/vital essential bacteria that don't need oxygen and live without it, meaning the rest of the oxygen can be used by other cells. In the presence of a lot of oxygen, pathogenic bacteria (disease causing), emerge and butyrate levels also go down.

 

In conclusion, the gut microbiome which consists of microbiota, has a great effect on the body, in a sense that the overall health of the microbiome can keep the homeostasis in the lungs and the rest of the body intact. In cases where there is a dysbiotic gut, we see lung diseases such as asthma, cystic fibrosis, idiopathic pulmonary fibrosis, and chronic obstructive pulmonary fibrosis just to name a few. It is important to also understand that to keep a healthy microbiome is to keep your diet, and mental/physical health in mind. To maintain homeostasis in organ health you need to eat healthy food, remember to keep your mental health in check, and that daily exercise is important.

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↳(H. A. Ziessman MD)

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↳(https://www.icliniq.com/doctor/dr-zubayeralam)

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↳( EDINA FREDELL, MPH, MT(ASCP), CIC)

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We would like to acknowledge:

• Mrs. Fauzia - She is our science teacher, and she helped us with figuring out our topic and new subtopics.
• Harrang Kaur - She was a lab nurse/ worker. She was also a teacher at Gobind Sarvar. She helped us with analyzing diagrams and understanding different types of bacteria.
• Karmanvir Kaur - She is a classmate of ours, and she helped us decided what subtopics we should use.
• Ms. Asli - She helped proof read our slides, and tell us with what mistakes we have.