Summary
The Drive podcast features an episode where Dr. Mike Gershon, a professor of pathology and cell biology at Columbia University, is interviewed by host Peter Etia. The discussion centers on the neural control of the gastrointestinal tract and the role of serotonin in the gut as a neurotransmitter. The gut is a tube that begins at the mouth and ends at the anus, and its inside is outside the body. The gut has to maintain a barrier and a surface to defend the body while allowing food to be digested and absorbed. During development, the body forms a flat disc that undergoes a series of folds to create an internal space that becomes the gut. The gut has to absorb a variety of nutrients and break down complex molecules without dissolving the body.
The gut is divided into three parts: foregut, midgut, and hindgut, which correspond to three major blood vessels. The gut has its own intrinsic nervous system, called the enteric nervous system, which can function independently of the brain and spinal cord. The gut is lined with epithelial cells that turn over about once a week. The paneth cell has defensive functions and produces antibacterial proteins to keep the small intestine sterile. The large intestine conserves sodium and water, which is important for organisms to live on land.
The gut plays an important role in regulating appetite through factors such as distension of the stomach, blood glucose levels, and hormones produced by endocrine cells. Gastric bypass surgery reroutes the upper GI tract, triggering the satiety signal and making eating less desirable. The Varicella Zoster Virus can become latent in nerve cells, causing a rash, but stays localized and doesn't give a systemic disease like chickenpox. The virus can also establish latency within the intrinsic nervous system of the gut, causing diseases such as pseudo-obstruction or achalasia.
The conversation covers various topics related to gut health and disease. The first part discusses alpha-1 antitrypsin deficiency, which can cause vascular and lung disease due to digestive action damaging organs. The discussion then moves on to leaky gut and its diagnosis, with milder leaks allowing toxins and microorganisms to enter the body. The relationship between leaky gut and autism spectrum disorder is also explored, with the conclusion that leaky gut is not related to the disorder.
The context discusses the importance of gut bacteria in determining obesity and immune system function. The same concept has been tested in humans through fecal transplants from lean to obese individuals. However, such experiments are difficult to conduct due to the complexity of the human microbiome. Fecal transplants are currently only approved for the treatment of C. difficile infections, but the procedure is not without risk as there are potentially lethal organisms in the gut. Synthetic biology is being explored as a way to create specific microorganisms for transplantation, but the technology is not yet advanced enough.
The speaker advises against particular diets or cleanses that may disrupt the microbiome. They also discuss the impact of artificial sweeteners and fatty acids on the microbiome. In terms of repopulating the gut after taking antibiotics, the speaker suggests taking appropriate probiotics. It is important to be cautious when choosing probiotics and to trust claims that have been evaluated by the FDA and FTC. Overall, the episode provides a comprehensive overview of the anatomy and physiology of the gut and its importance in maintaining overall health.
