Vitamins

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1. Nusrat jahan khan Id -1321022646

2. Imrul ShahedId-1320662046

3.Mashiqur RahmanId-1320661046

VITAMIN A

• A yellow, fat-soluble, solid terpene alcohol, obtained from carotene and occurring in green and yellow vegetables, egg yolk, etc.: essential to growth, the protection of epithelial tissue, and the prevention of night blindness.

FUNCTIONS

• Vision • Gene transcription • Immune function • Embroyonic development and reproduction • Bone metabolism • Haematopoieses• Skin health • Antioxidant activity

VITAMIN A Exits in 3 forms:

all trans-retinol long chain fatty acyl ester of retinol (main storage form) retinal (the active form in the retina)

Retinoic acid is also considered to be physiologically active Pro vitamin A or carotene can be converted to retinol in vivo

VISION CYCLE

Mechanism of Action

HYPERVITAMINOSIS A

• ACUTE:- caused by taking too much vitamin A over a short period of time

• CHRONIC:- occurs when too much of the vitamin A is present over a longer period

SYMPTOMS

• Abnormal softening of the skull bone (craniotabes -- infants and children)

• Bone pain or swelling• Bulging fontanelle

(infants)• Changes in

consciousness• Decreased appetite

• Headache• Increased intracranial

pressure• Irritability• Liver damage• Nausea• Poor weight gain • Skin and hair changes• Cracking at corners of

the mouth• Higher sensitivity to sunlight

DEFICIENCY OF VITAMIN A

• rickets • blindness• xeropthalmia • keratomalacia • bitot's spot • follicullar hyperkeratosis• xerosis conjunctiva • xerosis cornea

xeropthalmia KERATOMALACIA

BITOT'S SPOT

VITAMIN B

• B vitamins are a class of water-soluble vitamins that play important roles in cell metabolism. There are eight B-group vitamins, which are essential for bodily functions such as energy production and making red blood cells.

• The supplements which contain all eight are referred to as a vitamin B

complex . The eight B vitamins — B1, B2, B3, B5, B6, B7, B9, B12 — play an important role in keeping our bodies running like well-oiled machines. These essential nutrients help convert our food into fuel, allowing us to stay

energized throughout the day.

• The body has a limited capacity to store most of the B-group vitamins (except B12 and folate, which are stored in the liver). For this reason, it is important that adequate amounts of these vitamins be eaten regularly as part of a well-balanced, nutritious diet.

Sources of vitamin B

Types of vitamin B

1. Vitamin B1 (thiamine)

2. Vitamin B2 (riboflavin)

3. Vitamin B3 (niacin or nicotinic acid)

4. Vitamin B5 (pantothenic acid)

5. Vitamin B6(pyridoxine, pyridoxal, pyridoxamine)

6. Vitamin B7 (biotin)

7. Vitamin B9 (folic acid)

8. Vitamin B12(various cobalamins; commonly cyanocobalaminor methylcobalamin)

• Side effect :There are some reports of anaphylaxis caused by high-dose thiamin injections into the vein or muscle.

• Sources : Whole grains, peanuts, beans , blackstrap molasses and wheat germ

Thiamine

• Thiamine deficiency, causes beriberi., Wernicke's encephalopathy(impaired sensory perception), weakness and pain in the limbs,periods of irregular heartbeat, and edema (swelling of bodily tissues). Heart failure and death may occur in advanced cases.

B2 Deficiency, causes ariboflavinosis.

Symptoms may include cheilosis (cracks in the lips), high sensitivity to sunlight, angular cheilitis, glossitis(inflammation of the tongue), seborrheic dermatitis, pharyngitis (sore throat), hyperemia, edema of the pharyngeal and oral mucosa.

• Side effect : The only adverse effects associated with riboflavin comes from in vitro studies showing the production of reactive oxygen species(free radicals) when riboflavin was exposed to intense visible and UV light

• Sources : Almonds, wild rice, milk, yogurt, eggs, Brussels sprouts, spinach and soybeans.

Riboflavin

Sources : Yeast, red meat, milk, eggs, beans and green vegetables

Niacin Deficiency , along with a deficiency of tryptophan causes pellagra. Symptoms include aggression, dermatitis, insomnia, weakness, mental confusion, diarrhea.

In advanced cases, pellagra may lead to dementia and death (the 3(+1) Ds: dermatitis, diarrhea, dementia, and death).

Side effect: Intake of 3000 mg/day of nicotinamide and 1500 mg/day of nicotinic acid are associated with nausea, vomiting, and signs and symptoms of liver toxicity.

Nicotinic acid

Functions Niacin is composed of two structures: nicotinic acid and nicotinamide. There are two co-enzyme forms of niacin: nicotinamide adenine dinucleotide(NAD) and nicotinamide adenine dinucleotide phosphate(NADP).

• VITAMIN B6 DEFICIENCY, IS A SEBORRHOEIC DERMATITIS-LIKE ERUPTION, ATROPHIC GLOSSITIS WITH ULCERATION, ANGULAR CHEILITIS , CONJUNCTIVITIS , NEUROLOGIC SYMPTOMS OF SOMNOLENCE , NEUROPATHY,SIDEROBLASTIC ANEMIA

SIDE EFFECT : PYRIDOXINE IN EXCESS OF THE RDI OVER LONG PERIODS OF TIME RESULT IN PAINFUL AND ULTIMATELY IRREVERSIBLE NEUROLOGICAL PROBLEMS.

Sources : Chicken, turkey, tuna, salmon, sunflower seeds, cheese, brown rice and carrots

PLP

Vitamin B7 (biotin)Functions :Biotin plays a key role in the metabolism of lipids, proteins and carbohydrates.

It is a critical co-enzyme of four carboxylases: acetyl CoA carboxylase, which is involved in the synthesis of fatty acids from acetate; propionyl CoA carboxylase, involved in gluconeogenesis; β-methylcrotonyl CoA carboxylase, involved in the metabolism of leucin .

its association with healthy hair, skin and nails, It may help people with diabetes control high blood glucose levels

Biotin

Sources : Barley, liver, yeast, pork, chicken, fish, potatoes, cauliflower, egg yolks and nuts

Biotin Deficiency ,does not typically cause symptoms in adults but may lead to impaired growth and neurological disorders in infants.

Multiple carboxylase deficiency, an inborn error of metabolism, can lead to biotin deficiency even when dietary biotin intake is normal.

Sources :Dark leafy greens, asparagus, beets, salmon, root vegetables, milk, bulgur wheat and beans

Daily requirement : Adults need 0.2mg of folic acid a day.

Folic acid deficiency ,results in a macrocytic anemia, and elevated levels of homocysteine. Deficiency in pregnant women can lead to birth defects. Researchers have shown that folic acid might also slow the insidious effects of age on the brain.

Side effect : Folic acid can lead to permanent neurological damage.

Functions :Folic acid, known as folate in its natural form, is one of the B-group vitamins. Folic acid acts as a co-enzyme in the form of tetrahydrofolate(THF), which is involved in the transfer of single-carbon units in the metabolism of nucleic acids and amino acids.

folic acid

Sources : Fish, shellfish, dairy, eggs, beef and pork

Daily requirement :Adults need approximately

0.0015mg a day of vitamin B12.

B12 Deficiency , results in a macrocytic anemia, elevated homocysteine, peripheral neuropathy, memory loss and other cognitive deficits.autoimmune disease symptoms of mania and psychosis . In rare extreme cases, paralysis can result.

Side effect : Acne-like rash [causality is not conclusively established]

Vitamin C

• Also known as ascorbic acid• Water-soluble• Absorbed in intestine by an Na+ dependent

active transport (high concentrations use passive transport)

• Also regulated by the kidneys (conservation and excretion)

• Stored in pools throughout the body

Vitamin C

Source: http://biology.clc.uc.edu/courses/bio105/vitamin.htm

o It is readily absorbed from stomach & small

intestine

o Storage:o Only small amounts of vitamin C are stored

in the body (1 gm)

o It is present in the tissues as ascorbic acid &

dehydro ascorbic acid

o Mainly found in retina, adrenal gland,

pituitary & thymus

Metabolism

BIOCHEMICAL FUNCTIONS

• Collagen formation: Post translational modification-stabilisation and formation of collagen triple helix

• Bone formation

• Synthesis of serotonin (tryptophan)and homogentisic acid (tyrosine)

• Iron & Hb metabolism:Enhances absorption of ferrous form of iron;helps in Met Hb Hb bile pigments

• Maturation of erythrocytes

DEFICIENCY SYMPTOMS

SCURVY• Capillary fragility• Sore gums;loose teeth• Swollen joints &brittle bones• Fragile blood vessels• Impaired wound healing

• Anaemia & growth retardation• Immunocompetence• Subperiosteal & petechial haemorrhages

What is Vitamin D?

• Fat Soluble Vitamin• Found in food• Absorbed through sunlight exposure• Converted to hormone form through liver

and kidney

Two Major Forms of Vitamin D

• Vitamin D2, ergocalciferol

• Vitamin D3, cholecalciferol

Other Forms of Vitamin D• Vitamin D1: molecular compound of

ergocalciferol with lumisterol, 1:1• Vitamin D4: 22-dihydroergocalciferol

• Vitamin D5: sitocalciferol (made from 7-dehydrosisterol)

What are the sources?

• Exposure to sunlight• Cod Liver Oil, 1 Tbs: 1,360 IU• Salmon, cooked, 3 1/2 oz: 360 IU• Mackerel, cooked, 3 1/2 oz: 345 IU• Sardines, canned in oil, drained, 3 1/2 oz: 270 IU• Milk, nonfat, reduced fat, and whole, vitamin D fortified, 1 c: 98 IU• Margarine, fortified, 1 Tbs: 60 IU• Pudding, 1/2 c prepared from mix and made with vitamin D fortified

milk: 50 IU• Dry cereal, Vitamin D fortified w/10% of the recommended daily

value, 3/4 c: 40-50 IU (other cereals may be fortified with more or less vitamin D)

• Liver, beef, cooked, 3 1/2 oz: 30 IU• Egg, 1 whole (vitamin D is present in the yolk): 25 IU

What does Vitamin D do?

• Maintain normal blood levels of Calcium and Phosphorus

• Aids in absorption of calcium• Promotes bone mineralization• Prevents rickets in children and

Osteomalacia in adults

Role in immunomodulation

• Binds to nuclear Vitamin D receptors (VDR)

• Immune enhancing and immunosuppressive effects

• Increase activity of NKCs• Increased production of cathelicidin• Therepeutic Clinical Applications

When can vitamin D deficiency occur?

• Rickets• Osteomalacia

What is the health risk of too much vitamin D?

• nausea • vomiting • poor appetite • constipation • weakness • weight loss

A LITTLE ABOUT VITAMIN E...

Vitamin E is not a single substance but rather a family of fat soluble vitamins.

tocopherols: alpha tocopherol, beta tocopherol, gamma tocopherol, and delta tocopherol tocotrienols: alpha, beta, gamma, and delta tocotrienol Each vitamin has a specific function in the body. 

FOOD SOURCES OF VITAMIN E

• Asparagus• Avocado• Eggs• Milk• Nuts, such as almonds and hazelnuts• Seeds• Spinach and other green leafy vegetables• Unheated vegetable oils• Wheat germ• Wholegrain foods

FUNCTIONS IN THE BODY

• Protects your skin from ultraviolet light which promotes healthy skin and slows down the aging of skin

• Acts like an antioxidant and prevents cell damage from free radicals o  Free radicals are atoms or groups of atoms that can damage cellular

components such as DNA or parts of cells. • Prevents oxidative stress [when oxygen containing molecules

become too reactive] by preventing oxygen molecules from being too reactive

• Allows your cells to communicate effectively through a process called "cell signaling"

• Helps protect against prostate cancer and Alzheimer's disease

 

 

WHO

• People more than 55 years of age• Very low birth weight infants• Those who abuse alcohol and other drugs•  Those with: 

o cystic fibrosis o celiac diseaseo hyperthyroidismo malnutrition o liver, gallbladder, or pancreatic disease

RECOMMENDED DIETARY ALLOWANCES (RDAS) FOR VITAMIN E: • Infants, 0-6 months: 4 milligrams• Infants, 7-12 months: 5 milligrams• Males and females, 1-3 years: 6 milligrams • Males and females, 4-8 years: 7 milligrams • Males and females, 9-13 years: 11 milligrams • Males and females, 14 years and older: 15 milligrams • Pregnant females, 18 years and older: 15 milligrams • Lactating females, 18 years and older : 19 milligrams

DEFICIENCY SYMPTOMS AND EFFECTS• Difficult to pinpoint deficiency in Vitamin E • Fat malabsorption disorders are more likely to become

deficiento  The digestive tract requires fat to absorb vitamin E

• Problems that can arise from lack of Vitamin E are pancreatic disease, gallbladder disease, liver disease, and celiac disease. 

• Peripheral Neuropathy: people who lack Vitamin E may experience problems in their nervous system

DEFICIENCY SYMPTOMS AND EFFECTS CONT.

• Patients with Vitamin E deficiency may show signs and symptoms of hyporeflexia that progress to ataxia, including limitations in upward gaze.

• Patients with severe, prolonged vitamin E deficiency may develop complete blindness, cardiac arrhythmia, and dementia. 

• Patients may present with profound muscle weakness and visual-field constriction.

 

TOXICITY SYMPTOMS

Having too much Vitamin E can also be a problem.  If taken in excess amounts [3000 IU+] people may experience intestinal cramps and diarrhea, fatigue, double vision, and muscle weakness.

BIBLIOGRAPHY

1. http://www.whfoods.com/genpage.php?tname=nutrient&dbid=111  2. http://dietary-supplements.info.nih.gov/factsheets/vitamine.asp 3. http://emedicine.medscape.com/article/126187-overview

VITAMIN K Vitamin K is a group of lipophilic, hydrophobic vitamins.

They are needed for the postranslation modification of proteins required for blood coagulation,

They are involved in metabolism pathways, in bone mineralisation, cell growth, metabolism of blood vessel wall.

Vitamin K1

Vitamin K2

VITAMIN K

Vitamin K1 (phylloquinon) – plant origin

Vitamin K2 (menaquinon) – normally produced by bacteria in the large intestine

K1 a K2 are used differently in the body K1 – used mainly for blood clothing K2 – important in non-coagulation

actions - as in metabolism and bone mineralization, in cell growth, metabolism of blood vessel walls cells.

Synthetic derivatives of Vit.K

VITAMIN K - FUNCTION Cofactor of liver microsomal carboxylase which carboxylates glutamate

residues to g-carboxyglutamate during synthesis of prothrombin and coagulation factors VII, IX a X (posttranslation reaction).

Carboxylated glutamate chelates Ca2+ ions, permitting the binding of blood clotting proteins to membranes.

Forms the binding site for Ca2+ also in other proteins – osteocalcin.

PHYSIOLOGICAL EFFECTS OF VITAMIN K

Vitamin K serves as an essential cofactor for a carboxylase that catalyzes carboxylation of glutamic acid residues on vitamin K-dependent proteins. These proteins are involved in:

1) Coagulation2) Bone Mineralization3) Cell growth

Deficiencies are very rare in humans except in newborns due to:

• insufficient gut bacteria• poor placental transport of vitamin K• low prothrombin synthetic capacity of neonatal liver

Newborns routinely receive vitamin K injection (0.5 -1 mg vitamin K) or 2 mg orally, because human milk is very low in vitamin K (2.5 μg/L).

Bleeding episodes may occur in patients with low vitamin K status on

long-term antibiotic treatment (loss of colonic bacteria).

Vitamin K Deficiency

Vitamin K Deficiency

Hemorrhagic diseaseof the newborn

GI Bleeding

VITAMIN K - DEFICIENCY Deficiency is caused by fat malabsorption or by the liver

failure. Blood clotting disorders – dangerous in newborns, life-

threatening bleeding (hemorrhagic disease of the newborn).

Osteoporosis due to failed carboxylation of osteokalcin and decreased activity of osteoblasts.

Under normal circumstances there is not a shortage, vit. K is abundant in the diet.

SOURCES OF VITAMIN K

Green leafy vegetables vegetable oil broccoli cereals

http://health.allrefer.com/health/nutrition.html

COAGULATION

The transformation of liquid blood into a solid gel

Stops blood flow in the damaged area

Fibrin is the final protein which produces a meshwork to trap RBC and other cells

VITAMIN K DEPENDENT COAGULATION Certain clotting factors/proteins require calcium to bind for

activation

Calcium can only bind after gamma carboxylation of specific glutamic acid residues in these proteins

The reduced form of vitamin K2 (vitamin KH2) acts as a cofactor for this carboxylation reaction.

These proteins are known as “Vitamin K dependent” proteins

VITAMIN K DEPENDENT PROTEINS

factor II (prothrombin) factor VII (proconvertin) factor IX (thromboplastin component) factor X (Stuart factor) protein C & protein S Protein Z

CLOTTING CASCADE