ipl-logo

B12 Lab Report

2548 Words11 Pages

Chapter Vitamin B12 Absorption and Transport in Human Body Omar Abuyaman, MSc Department of Clinical Biochemistry, Aarhus University hospital, Aarhus, Denmark. Abstract Mammals are unable to synthesize B12. Instead, they have a sophisticated multistep pathway for specific and efficient transport of this vitamin from its food source to the target body cells. Dysfunction at any of transport steps may lead to low vitamin B12 status or deficiency. Introduction The transport of B12 from its food source to reach the body cells is mediated by a complex set of carrier proteins, receptors and transporters [1]. The selective multistep pathway of B12 transport, include the liberation of B12 from its matrix in the ingested food, gastrointestinal transport, …show more content…

The released B12 subsequently binds HC [12]. this binding is thought to shield the vitamin from chemical modification or hydrolysis by the acidic environment in the stomach. (Del Corral and Carmel 1990; Kittang and Schjonsby 1987) gastric dysfunction and diminished acid secretion (gastric atrophy, gastric surgery or treatment with acid suppressing drugs) may lead to B12 malabsorption. Different foods have different vitamin B12 bioavailability (the amount of vitamin B12 available for absorption) mainly depend on the ability of the stomach environment to liberate the vitamin from them. As example vib12 from the fish meat is less bioavailability than the B12 from the milk, mainly because of the limited ability for stomach conditions to liberate the bound B12 from its …show more content…

Cubam, on the other hand, recycles to the cell surface. Intrinsic factor is degraded by actions of lysosomal protease (most likely by cathepsin L enzyme which differ from the intestinal proteases) in the lysosome, [56].. and the Cbl is released, (inhibitors of lysosomal function block secretion of Cbl from cultured opossum kidney cells) [55]. Released vitamin B12 traverses the lysosomal membrane and enters the cytoplasm, a process that probably involves the protein LMBD1 and ABCD4. LMBD1 is a 61 kDa lipocalin receptor-like protein locate to the lysosomal membrane while the ABCD4 is ATP-binding cassette (ABC) transporter [41]. Mutations in the gene encoding LMBD1 or ABCD4 are responsible for the rare inborn defects named cblF and cblJ respectively with similar phenotype and clinical symptoms. Defects in LMBD1 or ABCD4 resulting in trapping of free vitamin B12 in lysosomes and therefore fail to absorb oral vitamin B12 [41] [42] . [43]. The mechanism of LMBD1 and ABCD4 contribution in the intracellular transport of vitamin B12 is currently unclear. However, because ABCD4 may co-localize with LMBD1 in the lysosomes it was proposed that the translocation mediated by LMBD1 and regulated by ABCD4. How B12 is handled within the cell from the point of lysosomal exit until its usage as a coenzyme or its export from the

Show More
Related

Unit 55 Body Weight Exercise

1143 Words | 5 Pages

55 body weight exercises can no where Get ready to General Do high reps with the weight may be valued on the basis of a couple of reasons as to fat labor. The muscle fibers are strands of muscle cramps in the middle of high reps. It thus will be eliminated from the body in the midst of low glycogen activity, have low glycogen. It is fundamental to fully absorb high muscle.

Read More

Vitamin Level 2 Unit 2

474 Words | 2 Pages

The recommended daily amounts or recommended daily allowances (RDA) are provided by different government agencies. Vitamins we can produce vitamin D which is formed in the skin from exposure to sunlight and vitamin K, B1, B12 and folic acid by intestinal flora but are too small quantities to meet the requirements. They are related mainly to the processes of formation or maintenance of tissue structures, immune processes and antioxidant activity. Of these, vitamins A and E participating in the protection of cellular and subcellular membranes, while vitamins D and K are involved in the synthesis of proteins specific linked to the metabolism of calcium and

Read More

Vitamin D Essay

1299 Words | 6 Pages

What is Vitamin D and Vitamin D Deficiency? Vitamin D is a steroid vitamin which promotes the abdominal absorption and ingestion of Ca (calcium) and P (phosphorus). Under normal conditions of an individual's exposure to sunlight, no dietary supplements are necessary because sunlight promotes sufficient vitamin D composition in the skin. Deficiency can lead to bone deformity in children and Osteomalacia in adults.

Read More

Puritan Research Paper

476 Words | 2 Pages

B3 - Niacin One of the main uses of niacin is to enhance the good cholesterol in the body. B5 - Pantothenic Acid Pantothenic comes from the Greek word pantothen, meaning “from everywhere.” it is in charge for the production of sex and stress hormones such as testosterone. Studies shows that Vitamin B5 also promotes healthy skin with the capacity to lessen signs of skin aging such as redness and skin spots. B6 - Pyridoxine

Read More

Multivitamin-Mineral Supplements

531 Words | 3 Pages

One of the easiest ways to determine if you need a multivitamin-mineral supplement is if you have fewer than 1600 kcalories. At first I wasn’t worried about overdosing on vitamins because I figured my body would just flush it out as well, but I was corrected again by Whitney and Rolfes. They illustrated that toxicity can go undetected in nutrients especially, iron, zinc, vitamin A, and niacin. 100% of our daily value is included for both vitamin A and zinc in the Alive supplement which makes it easier for someone to reach toxicity by eating a regular diet. In the Merk manual symptoms of vitamin A toxicity include drowsiness, irritability, abdominal pain, nausea, and vomiting.

Read More

Selenium Research Paper

909 Words | 4 Pages

It is also a basic component of various enzymes such as glutathione peroxidase (GSH-Px) and thioredoxin reductase (TR), which involve in the antioxidant protection of cells (Rotruck et al., 1973; Birringer et al., 2002). Deficiency

Read More

Susan Sullivan Vitamin A Summary

521 Words | 3 Pages

The article begins with the discussion of two types of vitamin A found in food called preformed and provitamin. Preformed vitamin A can be located

Read More

Ataxia Case Study

1161 Words | 5 Pages

9) Schuelke M, Mayatepek E, Inter M, Becker M, Pfeiffer E, Speer A, et al. Treatment of ataxia in isolated vitamin E deficiency caused by alpha-tocopherol transfer protein deficiency. J Pediatr

Read More

Research Paper On Eczema

375 Words | 2 Pages

When a liver cell is damaged the enzyme aspartate aminotransferase (AST), which is stored in the cytosol and mitochondria of liver cells, is released from the cell into the blood. (Mayo Clinic

Read More

Essay On Orlistat

1888 Words | 8 Pages

This risk is mitigated by an adequate diet or, exceptionally, by the daily intake of a multiple vitamin. Orlistat inhibits pancreatic carboxyl ester lipase, the enzyme necessary for hydrolysis of vitamin esters and absorption of fat soluble vitamins (Roche Pharmaceuticals, 1999; Hadvary et al., 1991, Ransac et al., 1991). During clinical trials, it decreased fat soluble vitamin absorption (Roche Pharmaceuticals, 1999; Davidson et al., 1999; Sjöström et al., 1998; Hollander et al., 1998, Hill et al., 1999). The effect is most notable with vitamins D and E and beta carotene (Roche Pharmaceuticals, 1999; McNeely and Benfield, 1998).

Read More

Vegan Diet Vs American Diet

1548 Words | 7 Pages

To inform, Harvard Health Publishing said that vegans are at a high risk of being deficient in vitamin B12 because plants do not provide this nutrient. All of these nutrients which vegans lack affect Americans’ growth and development, physical and mental well being, energy and increases their risk of developing health

Read More

Vitamin D Persuasive Speech

1055 Words | 5 Pages

The same thing applies to Vitamin D pills, till now no one knows what amount is safe and an overdose would lead to HyperCalcemia , which produces Kidney stones, meddles with your heart and brain, and damages your bones. Still, Vitamin D experts are increasing the daily amount needed well aware of the risks. So, some people opt for what they consider the safest way to get Vitamin D – Food. Vitamin D is commonly found in Dairy products , fatty fish, orange juice , egg yolks…etc. Nevertheless, one requires

Read More

Pros And Cons Of Veganism

823 Words | 4 Pages

When a person adopts a vegan diet, they will need to carefully plan what they eat to ensure they are getting the proper amounts of vitamins and nutrients. In particular, it can be common for people to develop a vitamin D deficiency. Sadly, it is also fairly common for people to underestimate the threat that can be posed by this condition. Vitamin D is essential for helping the body to absorb calcium. As a result, a prolonged deficiency of this vitamin can make a person more likely to suffer broken bones and an assortment of other health problems.

Read More

Importance For Bodybuilders

1022 Words | 5 Pages

Intense physical activity, however, disrupts the absorption of vitamin A and can exacerbate the already fragile state of the vitamin A levels bodybuilders might have. A low-fat intake can also affect vitamin A status. Vitamin A is Retained and Absorbed: Vitamin A and carotene can be lost in the faces of one who is on a low-fat diet as with a low fat intake very little bile gets to the intestine, where it helps to ensure that vitamin A is retained and absorbed. Vitamin A also helps regulate the immune system through helping lymphocytes, a type of white blood cell that fights infections, function more effectively. Further Aid: Some carotenoids have also been shown to function as antioxidants to fight free-radical build-up and further aid the immune system.

Read More

Argumentative Essay: Jogging Vs. Walking

1015 Words | 5 Pages

Then, who need health supplements? Active people strongly need health supplements, like athletes or outdoor workers. Other people who need health supplements are the ones who limit their daily intake, due to their beliefs like vegetarians, or suffer from diseases which ruins the digestive system in absorbing

Read More

More about B12 Lab Report

Open Document