Download MBBS (Bachelor of Medicine, Bachelor of Surgery) 1st year (First Year) Biochemistry ppt lectures Topic 11 Clinical Importance Of Enzymes Notes. - biochemistry notes pdf, biochemistry mbbs 1st year notes pdf, biochemistry mbbs notes pdf, biochemistry lecture notes, paramedical biochemistry notes, medical biochemistry pdf, biochemistry lecture notes 2022 ppt, biochemistry pdf.
Clinical Impor tance
of Enzymes
Clinical Importance of Enzymes
Disorders
Diagnosis of Diseases
Pharmacologic agents and Gene Therapy
Enzymatic Diseases
? Thousand of diseases occurs due to enzymatic defects
? Most of them are rare and inherited
- May affect Metabolic pathways: carbohydrate, lipid, proteins
- May affect Physiological processes like digestion
- May affect circulating enzyymes like antiproteases
Phenyl ketonuria
Phenylalanine
Phenylalanine Hydroxylase
Tyrosine
1 in 10000 live births
Mental Retardation
Albinism
Lactase Deficiency
? A very common disorder
? Milk indigestion
? Characterized by bloating, abdominal cramps and diarrhoea
Emphysema
? Due to 1 antitrypsin deficiency
? Inhibitor of serine protease- Elastase
? Neutrophilic elastase inhibits bacterial growth
? Elastase may damage lung tissue elastin if escapes
? Kept in check by antiprotease 1 antitrypsin
Diagnostic utility
Detection of Enzymes for diagnosis or
prognosis of disease
Enzymes as analytical agent
Detection of Enzymes for diagnosis of
disease
Disorders
Enzymes
Liver Function Tests
SGOT, SGPT, ALP, GGT
Cardiac Function Tests
CK-MB, Troponins
Pancreatic Enzymes
Amylase, Lipase
Muscle Enzymes
CK, LDH
Bone Enzymes
ALP , ACP
Plasma Functional Enzyme vs Plasma
Nonfunctional enzymes
Plasma functional Enzyme Plasma non-functional Enzymes
? Present in blood at all times
? Present in blood in minimal amounts
? Perform physiological functions in
? No known physiological function in blood
blood
? Eg. SGOT, SGPT, Amylase, CK-MB
? Eg. Lipoprotein lipase,
? Increased in diseased conditions due to
Pseudocholinesterase, Clotting factors
tissue damage, altered enzyme production
? Decrease in diseased conditions like
Liver disease
Isoenzymes
? Multiple forms of enzymes that catalyze the same reaction but differ in their
structure
? Encoded by different structural gene loci
? Differ in physical properties like electrophoretic motility or resistance to heat
inactivation
? Antigenically distinct
? Differ in catalytic properties like Km, Vmax.
? Shows Tissue specific distribution.
Examples of Isoenzymes
Enzyme
Isoenzymes
CK
CK-1 (CK-MM), CK-2 (CK-MB), CK-3 (CK-BB)
LDH
LDH 1-5
ALP
Hepatobiliary, Bone, Intestinal, Placental
Hexokinase
Hexokinase I-IV
Methods for Iso-enzyme detection
? Electrophoresis
? ELISA/Ag-Ab reactions
? Sequencing
? Susceptibility to Inhibitors/ Inactivation
Clinical Scenario 1
Jaundice
? A 69 years old male presented with abdominal pain. His LFTs showed
following results. His sclera was yellow and stools were pale with dark
colored urine.
Tests
Result
Reference Range
Bilirubin
6.0mg/dl
0.3-1.2mg/dl
AST
34 U/L
<50 U/L
ALT
35 U/L
<50 U/L
ALP
870 U/L
30 ? 120 U/L
Clinical Scenario 2
Jaundice
? A 35 years old male presented with malaise, weight loss, generalized
weakness. He noticed dark colored urine for past 2 days. LFTs were as
follows
Tests
Results
Reference Range
Bilirubin
2.5 mg/dL
0.3-1.2mg/dl
AST
900 U/L
<50 U/L
ALT
1200 U/L
<50 U/L
ALP
370 U/L
30 ? 120 U/L
Clinical scenario 3
MI
? A 50 year male presented to ED with tight chest pain radiating to left arm.
Cardiac function tests were as follows
Tests
Results
Reference Range
CK-Total
235 U/L
< 145 U/L
CK-MB
50 U/L
< 24 U/L
Troponin T
15 ng/L
< 10 ng/L
Enzymes as analytical reagents
? Measurement of Metabolites: Uricase, Urease, Glucose oxidase
? Immunoassays: ALP, Horse radish peroxidase, glucose 6 phosphate
dehydrogenase
? Recombinant DNA Technolog y: Restriction Endonuclease, DNA ligase,
DNA polymerase
Therapeutics
? Various drugs are used to inhibit enzymes therapeutically
Disorder
Enzyme
Drug
Cancer
Thymidylate Synthetase
5 fluorouracil
Inflammation
Cyclooxygenase
Aspirin
Gout
Xanthine oxidase
Allopurinol
Therapeutics
? Enzymes are also used as drugs
Disorder
Enzyme as Drug
MI
Streptokinase, tPA ( Thrombolysis)
Gaucher's disease
Glucocerebrosidase (ERT/Gene Therapy)
Cystic Fibrosis
Trypsin
Summar y
Disorders: Metabolic Pathways, Digestion, Circulating
Enzymes
Diagnosis of Diseases: Biomarkers, Analytical agents,
Recombinant DNA technology
Pharmacologic agents and Gene Therapy
This post was last modified on 05 April 2022