+

Dr. Beenish Zaki

Senior Instructor Department of Biochemistry

Vitamins and its nutritional aspect

+Objectives

B2, B6, Niacin, Biotin, Pantothenic acid, Vitamin C,E and K

Other names Active form Important function Deficiency disease

+Types of Vitamins

Water Soluble B1 B2 B6 Niacin Biotin Pantothenic acid Vitamin C

Fat Soluble Vitamin E Vitamin K

+Beri Beri

+B1 - Thiamine

Other name: Thiamine

Active form: Thiamine pyrophosphate

Function: Co-enzyme for Citric Acid cycle ,Hexose monophosphate pathway and Oxidation of branch chain amino acid .

Deficiency Disease: Beri Beri Wernike-korsakoff ( Most common in Alcoholics)

+Riboflavin deficiency

+B2- Riboflavin

Other name: Riboflavin

Active form: FMN, FAD

Function: Electron Transfer

Deficiency Disease: Angular stomatitis or Cheilitis Dermatitis

+B6

Other name: Pridoxine, Pyridoxamine, Pyridoxal

Active form: Pyridoxal phosphate

Function: Co-enzyme for amino acid metabolism

Deficiency Disease: Glossitis Neuropathy

+Tuberculosis and B6 Deficiency

Isoniazid is the first line treatment of Tuberculosis.

This drug can lead to deficiency of B6

Results in sensory neuropathy.

+Pellagra

+Niacin- 3 D’s

Other name: Nicotinic acid and Nicotinamide

Active form: NAD and NADP

Function: Electron transfer

Deficiency Disease: Pellagra Dermatitis Diarrhea Dementia

+Niacin and Hyperlipidemia

It is an alternative treatment for hyperlipidemia

+Biotin

Active form: Enzyme bound Biotin

Function: Carboxylation reactions

Deficiency Disease: Consumption of large amounts of raw egg whites. The egg whites have a protein called Avidin which binds biotin. This results in deficiency of Biotin.

+Pantothenic acid

Active form: Coenzyme A

Function: Acyl carrier

+Scurvy

+Vitamin C

Other name: Ascorbic Acid

Active form: Ascorbic Acid

Function: Antioxidant Coenzyme for hydroxylation in procollagen

Proline hydroxyproline Lysine hydroxylysine

+Vitamin C and Scurvy

The deficiency of vitamin C results in disease called Scurvy

It is characterized by: Sore spongy gums Loose teeth Poor wound healing

+

Fat Soluble Vitamin

+Vitamin K

Other name: Menadione, Menaquinone, Phylloquinone

Active form: Menadione, Menaquinone, Phylloquinone

Function: Gama-carboxylation of glutamate residue in clotting and other proteins.

Deficiency Disease: Bleeding

+Vitamin K deficiency and the neonates

Vitamin K is produced by Intestinal bacteria.

As the neonatal intestinal flora is not very well developed they do not produce vitamin K

This can result in bleeding in the neonates.

Intramuscular treatment with vitamin K is recommended at birth.

+Vitamins E

Other name: Alpha-Tocopherol

Active form: Several tocopherol derivatives

Function: Antioxidant

Deficiency Disease: Red blood cell fragility leading to hemolytic anemia.

+Overview

There are two major classes of vitamins Fat soluble Water soluble

Vitamins serve as mostly coenzymes in various reactions

The deficiency of vitamins can result in disease conditions such as Beriberi and Scurvy

Niacin can be used for treatment of hyperlipidemia

Vitamin K deficiency can manifest in the neonates which can be life threatening.

+Any Questions

+References

Lippincott 5th Edition

Images:http://www.blatner.com/adam/consctransf/historyofmedicine/5-deficiencydiseases/5-deficdis.html

http://www.rzuser.uni-heidelberg.de/~cn6/baltista/ribofl_e.htm