Pepsin is an powerful enzyme that breaks down proteins into smaller peptides.
Where is pepsin synthesized?
It is produced in the gastric chief cells of the stomach lining and is one of the main digestive enzymes in the digestive systems of humans and many other animals.
- Pepsin’s proenzyme, pepsinogen, is released by the gastric chief cells in the stomach wall, and upon mixing with the hydrochloric acid of the gastric juice, pepsinogen activates to become pepsin.
- The Optimum PH for pepsin: 1.5 to 1.6
Eating nourishing food is essential, but that food won’t benefit us if our body isn’t properly digesting it. Pepsin has very important role in digestion.
- So what is this digestion process?
Our body breaks down large food particles into smaller nutrients necessary to support growth and cellular repair; these nutrients also provide the body with the energy it needs to function. This process is known as food digestion. Digestion begins when food is eaten, and it ends when waste is excreted.
What is the role of pepsin in digestion?
When we are consuming protein foods like egg, meats, dairy products, nuts, pulses, these foods contain amino acids. Pepsin benefits digestion by dissolving their bonds of amino acids, thus breaking them into a smaller peptide or amino acid. This allows the nutrients that the food proteins contain to be more readily absorbed and assimilated by the small intestine.
Functions of Pepsin:
- Helps the body break down proteins that are hard to digest
- Prevents indigestion and leaky gut
- Stimulates the production of bile
- Supports the detoxification of the liver
- Boosts nutrient absorption
- Helps ward off nutritional deficiency
- Neutralizes the effect of enzyme inhibitors that are naturally present in foods such as egg whites, nuts, seeds, wheat germ, peanuts, potatoes and beans
- Kills bacteria in the stomach
- Separates vitamin B12 from protein so it can be effectively utilized by the body
Role of pepsin in absorption of Vitamin B12 in the gut:
Vitamin B12 is a well known water soluble vitamin necessary for a number of metabolic reactions and prevention of certain medical complications, most commonly hematopoietic disorders and spinal cord related neuropathies. As with any vitamin, human beings cannot synthesize or produce their own vitamins and thus must obtain them from dietary sources, bacteria making up our normal flora, and/or through supplements.
When it enters into the second segment of the duodenum, the pancreas will secrete additional protease, which will then degrade the R-binders holding onto the vitamin B12. Now at this point, the vitamin B12 will bind to (or complex with) intrinsic factor which is present in the gastric, for its journey to the ileum of the small intestine for absorption.
What is intrinsic factor?
- The intrinsic factor (IF) is a glycoprotein produced by the parietal cells (oxyntic cells) located at the gastric body and fundus. Intrinsic factor binds to vitamin B12 and thus plays a crucial role in the transportation and absorption of the vital micronutrient vitamin B12 (cobalamin) by the terminal ileum.
- If stomach does not make enough intrinsic factor, the intestine can not absorb vitamin B12, which can lead to Pernicious anemia because our body needs vitamin B12 to make red blood cells.
Vitamin B12 food sources: Meat, poultry, shellfish, eggs, dairy products
Antacids/PPI(Proton Pump Inhibitors) affects our gut health?
- Acid-reducing agents (ARAs) like antacids and proton pump inhibitors (PPIs) are some of the most common medications for the treatment of heartburn or indigestion. We consume this very frequently as quick-relief method in our day to day life, and most of the time without any medical consultations.
- Gastric acid plays an important role in digestion. Pepsin only works optimally in this acidic environment. Sometimes the contraction of muscles around the esophagus can cause gastric acid to back up into the esophagus from the stomach, causing a burning sensation to spread across the chest, known as acid reflux or heart burn.
- Recent study found evidence that long-term use of PPIs has harmful effects on gut health and microbiota. Researchers studied 36 patients who used PPIs for at least a year prior to the study. They also studied 36 non-users of PPIs as control subjects. Fecal samples from all of the participants were collected and analyzed. It was found that PPI users had a lower amount of Faecalibacterium in the gut. Faecalibacterium is one of the most abundant beneficial bacteria in the gut. This bacterium helps maintain intestinal health and guard against inflammation linked to gastrointestinal conditions, such as ulcerative colitis and Crohn’s disease (type of inflammatory bowel disease). Therefore, low levels of this beneficial bacterium can make the gastrointestinal tract susceptible to inflammation and infection.
- It was also discovered that the long-term use of PPIs encouraged the growth and spread of Streptococcus bacteria. Most of the species that belong to this genus are linked to infections like strep throat (a bacterial infection that causes inflammation and pain in the throat). Based on these findings it was concluded that the long-term use of PPIs affects the bacterial communities in the gut negatively.
Natural foods as antacids?
- Recent study discovered that incorporation of certain alkalinizing vegetables, fruits, milk and its products (broccoli, kale, radish, cucumber, lemon juice, cold milk and curd) alleviate hyperacidity by restoring the natural gastric balance and function, curb acid reflux, aid digestion, reduce the burning sensation due to hyperacidity and soothe the inflamed mucosa of the stomach.
- Their pH and neutralizing effect on gastric acid was determined and compared with water, the active control sodium bicarbonate and ENO.
- It was found that all test samples except lemon showed significantly higher (p<0.05 for cucumber and p<0.001 for the rest) acid neutralizing effect and a significantly (p<0.001) higher duration of consistent neutralization and higher antacid capacity than water.
- Highest antacid activity was demonstrated by cold milk and broccoli which was comparable with ENO and sodium bicarbonate. So it can be concluded that we can use natural food ingredients as essential dietary components to counter hyperacidity.
Effect of pepsin on harmful gut bacteria:
- The susceptibility of Escherichia coli (can cause severe stomach cramps, bloody diarrhea and vomiting through contaminated water and food) and Helicobacter pylori (can cause peptic ulcer by damaging the protective lining of the stomach and small intestine) to pH and the effect of pepsin-mediated proteolysis (breakdown of proteins into smaller polypeptides or amino acids) were investigated to establish the relative importance of their bacterial killing properties in gastric juice. It was found that killing of E. coli and H. pylori occurs optimally at pH of less than 2.5. And at pH 3.5, little effect is observed, whereas Addition of pepsin alone or in gastric juice causes a marked increase in bacterial susceptibility, suggesting an important role for proteolysis in the killing of bacteria.
Refrences:
https://www.naturalnews.com/2020-06-18-antacids-negatively-affect-gut-bacteria.html
