Vitamin D3 Presented by John Lear.

Slides:

Advertisements

Similar presentations

Department of Physiology

Advertisements

Biochemistry of Bone.

Got Calcium? Ca 2+. Plasma Calcium Regulation Plasma calcium totals 2.4 mM (9.4 mg/dl) –Free calcium is 1.2 mM.

Bone Disease in Renal Failure Dr Anne Kleinitz and Dr Cherelle Fitzclarence

Hormonal regulation of calcium and phosphorus homeostasis.

Calcium and phosphate homeostasis and hyperparathyroidism Charles Hand.

Regulation of calcitonin secretion Elevation of blood calcium –Response greater in male –Affected by age Declines as one ages Secretion by GI tract –Gastrin.

Chapter 19 Bone. A. Endocrine Control of Ca 2+ & PO 4 3-  __________________, 1,25-dihydoxy Vit D, & calcitonin control Ca 2+ and P levels & activities.

Ca ++ and P i Homeostasis. Ca ++ in the plasma [Ca ++ ] in plasma: 2.5 mM, of which about ½ is bound and thus physiologically inactive. Ratio of free/bound.

Endocrine Regulation of Calcium and Phosphate Metabolism

Importance of calcium: Ca ++ regulates: Neural function Muscle contraction Secretion of some hormones Blood clotting.

Endocrinology For each hormone, state the following: - name and location of secreting organ - chemical class and receptor type (where given) - target(s)

Homeostatic Regulation of Blood Calcium and Blood Glucose.

CALCIUM AND PHOSPHATE HOMEOSTASIS. Organs: Parathyroid Four oval masses on posterior of thyroid gland Develops from the 3 rd and 4 th pharyngeal pouches.

Diet intestine Stool Calcium pool Kidney Urine Bone mg 825 mg Absorbed 500 mg Secreted 325 mg Formation 280 mg reabsorption 280 mg Reabsorbed

By Dr. Sana Fatima Instructor, Biochemistry Department.

Vitamin D Dr.S.Chakravarty ,MD.

Chronic Kidney Disease-Mineral and Bone Disorder

Vitamin D, Rickets and Osteoporosis

DRUGS THAT AFFECT BONE MINERAL HOMEOSTASIS

Copyright © 2006 by Elsevier, Inc. Microscopic Appearance of the Thyroid Gland Figure 76-1; Guyton & Hall.

Lecture # 12: Calcium homeostasis

PARATHYROID HORMONE (PTH). SOURCE SYNTHESIS 1. Preprohormone=110 A.A. 2. Prohormone= 90 A.A. 3. Hormone= 84 A.A.( Mol.wt.=9500)

7-1 Mineral Deposition Mineralization is crystallization process –osteoblasts produce collagen fibers spiraled the length of the osteon –minerals cover.

Calcium Metabolism, Homeostasis & Related Diseases.

Phayrngeal Region Endocrine Glands Parathyroid Control of Calcium Homeostasis.

Vitamin D. Vitamin D & metabolites are steroids D 3 is the most active metabolite D 3 is a product of Vitamin D metabolism in the liver and kidney D 3.

PTH Calcitonin 10mg% Vitamin D Lecture 52 Ca++ Homeostasis

Vitamin D, Rickets and Osteoporosis

Bone Homeostasis.

Chapter 9 The Fat-Soluble Vitamins. Copyright 2010, John Wiley & Sons, Inc. Fat-Soluble Vitamins Vitamins A, D, E and K are fat-soluble vitamins. Fat-soluble.

Parathyroid Gland & Calcium Metabolism

Parathyroid Glands Physiology Dr Taha Sadig Ahmed.

Calcium, Phosphorus, Magnesium and Related Disorders (By Basil OM Saleh) Objective: 1. Calcium & Phosphorus homeostasis, Hypercalcaemia, and Hypocalcaemia.

VITAMIN D T Like a hormone Its Role in Calcium Homeostasis.

Parathyroid hormone(Parathormone) Lecture NO: 2nd MBBS

MLAB 2401: Clinical Chemistry Keri Brophy-Martinez

Calcitonin Calcitonin By: Narjes lavasani.

Hormones that affect metabolism: Thyroid Gland

Pharmacology of drugs used in calcium & vitamin D disorders

Parathyroid Gland & Calcium Metabolism

Bone Metabolism MSS/Biochemistry, fall-2017

Pharmacology of drugs used in calcium & vitamin D disorders

Hormonal Regulation of Growth, Development, and Metabolism

Negative feedback regulation of parathyroid hormone (PTH) release

PARATHYROID AND CALCIUM HOMEOSTASIS

Drugs for osteoporosis (download the lecture from

Vitamin D metabolism and physiologic effects at target organs

Vitamin D is a group of fat-soluble secosteroids responsible for intestinal absorption of calcium and phosphate. It is not actually an essential dietary.

Hormones & The Endocrine Glands

By: Rachel joya, Erinn Sinn

Hormonal control of calcium and phosphate metabolism

High Prevalence of Vitamin D Inadequacy and Implications for Health

Dr. Shaikh Mujeeb Ahmed Assistant Professor AlMaarefa College

1 ENDOCRINE PHYSIOLOGY PSL 223 PSL 223. Dr. S.Bashir2 Objectives By the end of this part of the course the student should be able to: By the end of this.

Vitamin D and the Parenteral Nutrition Patient

Clinical Chemistry of Parathyroid disorders

Osteomalacia and Rickets

High Prevalence of Vitamin D Inadequacy and Implications for Health

The Parathyroid Gland By Jonah Carleton, & Elise Voorhis

The major function of the parathyroid glands is to maintain the body's calcium level within a very narrow range, so that the nervous and muscular systems.

Parathyroid hormone(Parathormone) Lecture NO: 2nd MBBS

Chapter 10 FAT-SOLUBLE VITAMINS

Osteoblasts Osteocytes Osteoclasts Cells of Bone Osteoblasts Osteocytes Osteoclasts.

Peripheral Glands.

Volume 71, Issue 8, Pages (April 2007)

The ins and outs of phosphate homeostasis

Control of uremic bone disease: Role of vitamin D analogs

Regulation of serum calcium homeostasis.

Presentation transcript:

Vitamin D3 Presented by John Lear

Vitamin D3: The Basics A fat-soluble vitamin: C27H44O Sources: Skin, Diet Active form: Calcitriol - steroid hormone Overall effect: ↑Ca2+ in blood Vitamin D2: from plants, not as efficient

Cholesterol Precursor (in skin) Structure Cholesterol Precursor (in skin)

(prohormone) Calcitriol 1,25(OH)2D3

Vitamin D3 Pathway

Vitamin D Binding Protein

Vitamin D Receptor (VDR) A type of “Nuclear Receptor”

Vitamin D Receptor (VDR)

Effects of ↑Calcitriol? (Hint: ↑Ca2+!) Intestines ↑Absorption of Ca2+ (↑calbindin) ↑Absorption of PO4- ↑Absorption of Mg2+ Parathyroid Glands ↓PTH Synthesis ↓PTH Secretion 3. Bone ↑Ca2+ Resorption from bone 4. Kidneys ↑Ca2+ Reabsorption in tubules Auto-regulation (negative feedback) of Calcitriol production

Regulation of Calcitriol

“Permissive Effect”

↓Phosphorus - - ↑Phosphorus +

Vitamin D Abnormalities Normal Blood Vitamin D levels: 20- 50 ng/ml Vitamin D Abnormalities Vitamin D Deficiency Rickets (children) Osteomalacia (adults) Secondary Hyperparathyroidism May lead to: Depression Greater risk of cancers

Vitamin D Abnormalities Normal Blood Vitamin D levels: 20- 50 ng/ml Vitamin D Abnormalities Vitamin D Toxicity Calcium Kidney Stones Bone Pains Gastrointestinal Pains Psychological problems

In Summation Vitamin D3 Active form is Calcitriol Primary action: increase intestinal Ca2+ absorption Closely linked with PTH for Ca2+ and PO4- regulation

Thank you! Sources: http://themedicalbiochemistrypage.org/vitamins.php#d https://www.youtube.com/channel/UCGL_VmFb7IUr-4z5anXtCPw (Dr. David Cohen - Medical Education)