• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Vitamins
 

Vitamins

on

  • 219 views

good

good

Statistics

Views

Total Views
219
Views on SlideShare
219
Embed Views
0

Actions

Likes
0
Downloads
9
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Vitamins Vitamins Presentation Transcript

    • VITAMIN- A M.Prasad Naidu MSc Medical Biochemistry, Ph.D,.
    • VITAMIN- A  Structure 6C beta-ionine ring with 11C polyprenoid side chain with alternate double bonds.  Provitamin–beta carotene [Retinal+Retinal]  Active forms 1.Retinol 2.Retinal 3.Retinoic acid
    • CH 3 CH 3H 3C CH 3 CH 2OH CH 3 VITAMIN A (RETINOL) RDA: 0.7 mg Poly isoprenoid side chain
    • VITAMIN A  Retinol Retinal retinoicacid All-trans Retinal common in circulation.  11cis- Retinal form is present in rhodopsin.  Active forms are heat stable and light sensitive.
    • VITAMIN A  Sources Animal –marine fish liver oils Plant - mangopapayacarrot  RDA – 1000 ug day 1 RE = 1ug of retinol = 0.6 ug of betacarotene
    • VITAMIN A
    • . FUNTIONS 1. Retinal and Retinol vision 2. Retinoic acid – cell differentiation glycoprotein synthesis reproduction. 3.Beta-carotene- Anti-oxidant
    • WALDS VISUAL CYCLE  The Cyclic events that occur in the process of vision is visual cycle. .  Rhodopsin is a photoreceptor present in retinal rod cells.  Rhodopsin is a conjugated protein with 11-cis retinal and protein opsin.
    • FUNCTIONS OF VIT A WALDS VISUAL CYCLE
    • DEFECIENCY primary causes [dietary] secondarycauses[malabsorption] Results in Night blindness Conjunctival xerosis Bitots spots Corneal xerosis keratomalasia Blindness
    • .  Toxicity of vit-A is either due to 1. over-dosage of vit-A supplements 2. excess dietary intake [  As vitamin A is not excreted from the body it isccumulated in liver producing toxic effects  Toxicity produces headache , nausea , vomitings , liver damage alterations in the skin and mucous membranes etc.
    • .  Vit-A can be used to treat diseases where epithelial surface is damaged.  Retinoic acid acts on cell differentiation and growth therefore used as a drug.  It is used to treat diseases like Measles, Acne, Psoriasis , Leukemia etc.
    • VISUAL CYCLE meta-rhodopsin Transducin Transducin [A] PDE PDE [A] CGMP GMP
    • VISUAL CYCLE Decreased CGMP closes Na+ channels in rod cell membrane hyper polarization of rod cell membrane generation of nerve impulse to visual cortex
    • VITAMIN D  Structure plants - Ergosterol Ergocalciferol [D2] Active form in animals is calcitriol UV
    • VITAMIN D  Sources 1. sunlight 2. animal sources; fish liver oils eggs 3. plant sources 4. food fortification ; milk butter  RDA 200-400 IU day
    • VITAMIN D  Digestion absorption transport Digested and absorbed in small intestine using bile salts . Vit-D is transported from intestine to circulation by chylomicrons and stored in the liver.
    • VITAMIN D  Synthesis of vit-D  Regulation of synthesis by Ca and PO4.  Low calcium stimulates PTH secretion which activates 1- hydroxylase
    • FUNCTIONS Vit-D plays a major role in regulation of calcium and phosphate levels by mainly acting on 3 different organs.  Intestine ; increases absorption of Ca and PO4  Bone ; increases deposition of CaPO4 thus increasing mineralization of bones .  Kidneys ; reabsorbs Ca and decreases Ca excretion.
    • VITAMIN D  Deficiency Children ---Rickets Adults ------ Osteomalacia
    • VITAMIN D  Toxicity hyper-vitaminosis D causes toxic effects like de-mineralization , hyper-calcemia , renal calculi etc.
    • ABSORPTION AND TRANSPORT
    • IRON DEFICIENCY ANEMIA  Laboratory findings  Hypochromic microcytic anemia  ferritin ( 30 to 300 Nanogm/ml)  serum iron (50 to175 µgm/dl)  TIBC (300 to 350 µgm/dl)  transferrin (200 to 400 mg/dl) Spoon-shaped nails (koilonychia)
    • Dental fluorosis
    • THANK Q