Disorders of Calcium and Phosphate Metabolism

Disorders of Calcium and Phosphate Metabolism

Outline
* Review of calcium and phosphate metabolism
* Abnormalities of calcium balance
* Abnormalities of phosphate balance
* Example cases

Major Mediators of Calcium and Phosphate Balance
* Parathyroid hormone (PTH)
* Calcitriol (active form of vitamin D3)

Role of PTH
* Stimulates renal reabsorption of calcium
* Inhibits renal reabsorption of phosphate
* Stimulates bone resorption
* Inhibits bone formation and mineralization
* Stimulates synthesis of calcitriol
Net effect of PTH
Regulation of PTH
Role of Calcitriol
* Stimulates GI absorption of both calcium and phosphate
* Stimulates renal reabsorption of both calcium and phosphate
* Stimulates bone resorption

Net effect of calcitriol
Regulation of Calcitriol
Overview of Calcium-Phosphate Regulation
Different Forms of Calcium
Calcium in the plasma:
Overview of Biochemical Homeostasis
Overview of Calcium Balance
Etiologies of Hypercalcemia
Increased GI Absorption
Milk-alkali syndrome
Elevated calcitriol
Vitamin D excess
Excessive dietary intake
Granuomatous diseases
Elevated PTH
Hypophosphatemia

Increased Loss From Bone
Increased net bone resorption
Elevated PTH
Hyperparathyroidism
Malignancy
Osteolytic metastases
PTHrP secreting tumor
Increased bone turnover
Paget’s disease of bone
Hyperthyroidism
Decreased Bone Mineralization
Elevated PTH
Aluminum toxicity
Decreased Urinary Excretion
Thiazide diuretics
Elevated calcitriol
Elevated PTH
Etiologies of Hypocalcemia
Decreased GI Absorption
Decreased Bone Resorption/Increased Mineralization
Increased Urinary Excretion
Overview of Phosphate Balance
Etiologies of Hyperphosphatemia
Increased GI Intake
Decreased Urinary Excretion
Cell Lysis
Etiologies of Hypophosphatemia
Decreased GI Absorption
Decreased Bone Resorption / Increased Bone Mineralization
Increased Urinary Excretion
Internal Redistribution (due to acute stimulation of glycolysis)
4 Case stuides

Disorders of Calcium and Phosphate Metabolism.ppt

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Overview of carbohydrate metabolism

Overview of carbohydrate metabolism
Presentation by: Dr. Nuran Ercal

GLYCOLYSIS
* Glycolysis occurs in almost every living cell.
* It occurs in cytosol.
* It was the first metabolic sequence to be studied.
* Most of the work done in 1930s by the German biochemist G. Embden Meyerhof Warburg.
* That is why it is also called Embden-Meyerhof pathway.
* It is a greek word.
* Glykos------> sweet
* Lysis-------> loosing
* Glycolysis-----------> loosing or splitting of glucose
* Glc is an important fuel for most organisms.
* Why is Glc chosen?
* 1) Glc is one of the monosaccarides formed formaldehyde
* under prebiotic conditions.
* 2) Glc has a low tendency to glycosylate proteins
* Fermentations provide usable energy in the absence of oxygen
* Why is a relatively inefficient metabolic pathway so extensively
* used?
* Answer: It does not require oxygen
* Obligate anaerobes
* Facultative anaerobes
* 3 of the reactions of glycolysis are irreversible.
* Pyruvate is the end product of glycolysis in tissues with mitochondria.
* This series of 10 reactions called aerobic glycolysis,

Stages of glycolysis
* Stage I
* Goal: To trap the Glc in the cell

IMPORTANCE OF PHOSPHARYLATED INTERMEDIATES
PHOSPHORYLATION OF GLUCOSE
Induced fit in Hexokinase
Difference between hexokinase and glucokinase
Hexokinase vs glucokinase
SUMMARY
More about HK
* Hexokinase, like adenylate kinase and all other kinases, requires Mg (or Mn) for activity.
* Hexokinase is also one of the induced-fit model enzymes.
* It has two lobes that move towards each other when Glc is bound!
* Substrate-induced cleft closing is a general feature of kinases.
* Other kinases (Pyruvate kinase, phosphoglycerate kinase and PFK) also contain clefts between lobes that close when substrate is bound.

2. ISOMERIZATION OF G-6-P
3. PHOSPHORYLATION OF F-6-P
4. CLEAVAGE OF F-1,6BIP
5. ISOMERIZATION OF DIHYDROXYACETONE-P
6. OXIDATION OF GLYCERALDEHYDE 3-P.
Structure of glyceraldehyde 3-phosphate dehydrogenase
7: FORMATION OF ATP FROM 1,3-BIPGLYCERATE AND ADP
Q:Why does PEP have such a high P-ryl potential?
Pyruvate kinase deficiency:
Maintaining redox balances

Overview of carbohydrate metabolism.ppt

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Carbohydrate Metabolism

Carbohydrate Metabolism

An Overview of Metabolism
Anabolism
Catabolism
Cells and Mitochondria
Metabolism of Carbohydrates
Blood Glucose Homeostasis
Fates of Glucose
High Blood Glucose
Glucose absorbed
Insulin: Glucagon
Pancreas
Muscle
Adipose
Cells
Glycogen
Glucose Metabolism
Fate of Absorbed Glucose
Glucose Utilization

Glucose
Pyruvate
Ribose-5-phosphate
Glycogen
Energy Stores
Pentose Phosphate Pathway
Glycolysis
Adipose
Glycogenesis
Lactate (animals)
Acetyl-CoA (TCA cycle)
Ethanol (yeast)
Adenosine Tri-Phosphate (ATP)
Mechanisms of ATP Formation
Phosphocreatine + ADP
Creatine + ATP
First Reaction of Glycolysis
Glycolysis - Summary
Pyruvate Metabolism
Anaerobic Metabolism of Pyruvate
Pyruvate Metabolism - Anaerobic
TCA Cycle
Oxidative Phosphorylation
Oxidation and Electron Transport
Electron Transport Chain
Total ATP from Glucose
Volatile Fatty Acids
Effect of VFA on Endocrine System
Glycolysis
Energy Storage
and much more are covered in this.ppt

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Drug Metabolism

Drug Metabolism

Transformation of Xenobiotics by Biological Systems
IMPLICATIONS FOR DRUG METABOLISM
1. Termination of drug action
2. Activation of prodrug
3. Bioactivation and toxication
4. Carcinogenesis
5. Tetratogenesis

Termination of Drug Action
Activation of Prodrug
Factors Affecting Drug Metabolism

* Age
* Diet
* Genetic Variation
* State of Health
* Gender
* Degree of Protein Binding
* Species Variation
* Substrate Competition
* Enzyme Induction
* Route of Drug Administration
Organ Sites of Drug Metabolism

* Liver
* Small intestine
* Kidney
* Skin
* Lungs
* Plasma
* All organs of the body
Cellular Sites Of Drug Metabolism
KINETICS OF DRUG METABOLISM
Velocity Of Metabolism Of A Drug
Velocity Of Metabolism Of Three Drugs
Phase of Metabolism
Phase I Reactions
Phase II Metabolism
Patterns of Drug Metabolism
PHASE I METABOLIC PATHWAYS
CONVERSION OF TERFENADINE TO FEXOFENADINE
* The Pharmacological Basis of Therapeutics
CIMETIDINE Inhibits CYP450 Metabolism Of Many Drugs
Monoamine Oxidase Metabolism of Serotonin
Diamine Oxidase
Alcohol Dehydrogenase
Xanthine Oxidase
Nitro Reduction
Azo Reduction
Microsomes and cytosol
Amide Hydrolysis
Microsomes and cytosol
Ester Hydrolysis
Microsomes and cytosol
Epoxide Hydrolase

PHASE II METABOLIC PATHWAYS
PHASE II REACTIONS
GLUCURONIDATION
Morphine Metabolism

and much more are covered in this presentation

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Glycogen Metabolism

Glycogen Metabolism
Copyright © 1999-2007 by Joyce J. Diwan.

Topics discussed:
Biochemistry of Metabolism
Glycogen is a polymer of glucose residues linked by
Glycogen catabolism (breakdown):
Pyridoxal phosphate (PLP)
A glucose analog, N-acetylglucosamine (GlcNAc)
Glycogen Phosphorylase
Explore the structure of muscle Glycogen Phosphorylase with Chime.
Phosphoglucomutase catalyzes the reversible reaction
Glycogen synthesis
Glycogenin initiates glycogen synthesis.
Glycogen Phosphorylase in muscle
Regulation by covalent modification (phosphorylation)
The hormones glucagon and epinephrine
Commonly used terminology
Explain Symptoms:
Glycogen Synthase

Glycogen Metabolism.ppt

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Lipoprotein Metabolism

Lipoprotein Metabolism
Presentation by: Jack Blazyk

Lipids in the Blood
Role of Cholesterol
Metabolism of Cholesterol
Anatomy of a Lipoprotein
Apolipoproteins
Adipose tissue
Albumin / free fatty acids
Liver, intestine, VLDL, chylomicrons
Triacylglycerol, cholesterol
Main Lipid Components
Triglyceride-Degrading Enzymes
Enzymes and Transfer Proteins
Clinical Implications of Lipoproteins
Blood Lipid Levels
Genetic Disorders
Statins
New Drugs Beyond Statins

Lipoprotein Metabolism.ppt

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Lipids Metabolism

Lipids Metabolism
Presentation by

AKRAM GASMELSID ABDALLA MUKHTAR
TAN CHEE KHUAN
TEY GIM CHONG
CHEK YIN HUAY

Objectives

* To determine the interrelationship between the lipids intake and human physiology
* To analyze how different individual and gender react to different amount of intake
* To identify the optimal intake to prevent exceeding and shortage of lipids in diet

Definition of Lipids
Type of Lipids
Lipids Functions
Lipids Disorder
Lipids Deficiency
Lipids Exceeding
Body Mass Index
Obese
Health Problems
Cholesterol
Lipoproteins
Blood levels for Lipids
Simulator
Simulation
Compartmental Analysis
Prevention of Lipid Disorder

Lipids Metabolism.ppt

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Glucose Metabolism in the b-Cell

Glucose Metabolism in the b-Cell
Tutorial by: Richard Bertram

Metabolites as Signaling Molecules
Three Steps Involved in Glucose Metabolism
Glycolysis
Energy is Invested at the Beginning of Glycolysis
Energy is Generated During Second Step
What is the Mechanism for Glycolytic Oscillations?
Model Glycolytic Oscillations
Glycolytic Oscillations Occur Only for Moderate GK Rates
Citric Acid Cycle
Coenzymes are Produced by the Citric Acid Cycle
Anaplerosis and Cataplerosis
Anaplerosis Involving Pyruvate
Anaplerosis Involving Amino Acids
Cataplerosis of Citrate
Subway Analogy
Citric Acid Cycle
The Malate/Aspartate Shuttle
Oxidative Phosphorylation
Elements of Oxidative Phosphorylation
Mitochondrial Variables: NADH concentration
The NADH Equation
The ADP/ATP Equations
The Inner Membrane Potential Equation

Metabolism.ppt
http://www.math.fsu.edu/~bertram/presentations/workshops/MBI_07/Metabolism.ppt

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