BIOCHEMISTRY-Metabolism Flashcards
These are the two sites where the metabolism takes place
Mitochondria and Cytoplasm
These three process take place in the mitochondria and the cytoplasm
Heme synthesis, Urea cycle, Gluconeogenesis
Name the processes that take place in the mitochondria
Fatty acid oxidation (β oxidation)
Acetyl CoA production, TCA cycle
Oxidative phosphorylation
Which processes take place in the cytoplasm?
Glycilysis Fatty acid synthesis HMP shunt Protein synthesis Steroid synthesis Cholesterol synthesis
What does Glucokinase catalyzes?
Catalyzes the phosphorylation of glucose using a molecule of ATP
What is the function of Kinase?
Uses ATP to add high energy phosphate group onto substrate
This enzyme adds inorganic phosphate onto substrate without using ATP
Phosphorylase
What does the Phosphatase does to the substrate?
removes phosphate group
This enzyme catalyzes oxidation reduction reactions
Dehydrogenase
What does Hydroxylase does to the substrate?
Adds hydroxyl group (-OH)
Which is the effect of Carboxylase?
Transfers CO2 groups with help of biotin
This enzyme relocates a functional group within a molecule
Mutase
This enzyme manages the glycolysis
Phosphofructokinase-1 (PFK-1)
Who are the positive regulators of PFK-1
AMP +
Fructose- 2, 6- biphosphate +
These are the negative regulators of PFK-1
ATP -
citrate -
Which process is fructose-1,6 biphosphatase related?
Gluconeogenesis
ATP and acetyl-CoA which kind of regulators are for fructose-1,6 biphosphatase?
positive regulators
These are the negative regulators for fructose-1,6 biphosphatase
AMP -
Fructose- 2, 6- biphosphate -
Which are the alternative names for Citric acid cycle?
Tricarboxylic acid cycle (TCA) or Krebs cycle
This enzyme has a great importance on TCA cycle
Isocitrate dehydrogenase
This is the positive regulator in Citric acid cycle
APD+
Who are the negative regulators in Krebs cycle?
ATP- and NADH
This enzyme manages the glycogenesis
Glycogen synthase
These are positive regulators in glycogenesis
Glucose-6-phosphate
Insulin
Cortisol
Epinephrine and glucagon are negative regulators in this process
Glycogenesis
Which process is managed by glycogen phosphorylase?
Glycogenolysis
Glucose-6-phosphate, Insulin and ATP are negative regulators for this process
Glycogenolysis
Who are positive regulators in Glycogenolysis?
AMP, Epinephrine and glucagon
This enzyme is related to hexose monophosphate shunt…
Glucose-6-phosphate dehydrogenase (G6PD)
Is NADP a positive or negative regulator in pentose phosphate pathway?
Positive
It´s an alternative name for hexose monophosphate shunt…
Pentose phosphate pathway
Is NADPH a positive or negative regulator in hexose monophosphate shunt?
Negative
Which process is Carbamoyl phosphate synthetase II related to?
De novo pyrimidine synthesis
This enzyme is related to De novo purine synthesis
Glutamine-phosphoribosylpyrophosphate (PRPP) amidotransferase
These are negative regalutors in De Novo purine synthesis
AMP, IMP, GMP
The carbamoyl phosphate synthetase I is related to this process
Urea Cycle
The N-acetylglutamate is a positive regulator in this process
Urea cycle
Which enzyme is related to fatty acid oxidation?
Carnitine acyltransferase I
Who is a negative regulator in Fatty acid synthesis?
Glucagon and palmitoyl-CoA
Act as an enzyme in the Fatty acid synthesis
Acetyl CoA carboxylase (ACC)
Insulin and citrate are postive regulators in fatty acid oxidation or fatty acid synthesis
In the fatty acid synthesis
Which process has HMG- CoA synthase as an enzyme?
Ketogenesis
Which enzyme acts in Cholesterol synthesis?
HMG- CoA reductase
Insulin and Thyroxine are positive regulators in this process
Cholestherol synthesis
Which are the negative regulators in Cholestherol synthesis?
Glucagon, cholesterol
How many ATP are produced in the aerobic metabolism via malate aspartate shuttle?
32 net ATP
Which organs are related to aerobic metabolism via malate aspartate shuttle?
Heart and liver
How many ATP are produced in the aerobic metabolism via glycerol 3 phosphate?
30 net ATP
Which tissue is related to aerobic metabolism via glycerol 3 phosphate?
Muscle
How many ATP are produced in the anaerobic glycolysis?
2 net ATP per glucose molecule
Can ATP hydrolysis be coupled to energetically favorable reactions?
False, ATP hydrolysis can be coupled to energetically unfavorable reactions
Which element causes glycolysis to produce zero net ATP?
Arsenic
From which pathway is NADPH produce?
HMP shunt
Where is used NADPH?
Anabolic processes
Respiratory burst
Cytochrome P450 system
Glutathione reductase
In which processes is NAD+ generally used?
Catabolic processes
During the catabolic processes which is the function for NAD+ ?
To carry reducing equivalents away as NADH
In which processes is NADPH generally used?
Anabolic processes
These are examples of anabolic processes
Steroid and fatty acid synthesis
During the anabolic processes which is the function for NADPH?
As a supply of reducing equivalents
Which is the first step of glycolysis?
Phophorylation of glucose to yield glucose 6-P
In which other process Phophorylation of glucose to yield glucose 6-P is the first step?
Glycogen synthesis in the liver
Which enzyme catalyses Phophorylation of glucose to yield glucose 6-P?
Hexokinase or glucokinase depending in the tissue
At low glucose concetrations who sequesters glucose in the tissue?
Hexokinase
When there is high glucose concentration, who stores glucose excess?
The liver
These are the location of action of the Glucokinase
Liver, β cells of pancreas
Which are the location of action of the Hexokinase?
Most tissues, but not Liver nor β cells of pancreas
What is the difference in Km between Hexokinase and Glucokinase
Hexokinase has lower Km but ↑ affinity
and Glucokinase has Higher Km but ↓ affinity
For the Glucokinase what does it meas that has Higher Km but ↓ affinity?
This means that it operates only when serum glucose levels are high.
If tissues need to use glucose at lower serum levels which enzyme is used?
Use the higher affinity (lower Km) hexokinase
How is the Vmax in the Hexokinase
Lower and decrease Capacity
Higher V max with increase capacity…. Glucokinase or Hexokinase?
Glucokinase
Feedback inhibited by glucose 6 P….Glucokinase or Hexokinase?
Hexokinase
Gene mutation associated with maturity onset diabetes of the young… Glucokinase or Hexokinase?
Glucokinase
Which is the equation in the net glycolysis?
Glucose+ 2Pi+ 2ATP+ 2 NAD→ 2 pyruvate+ 2 ATP+ 2 NADH+ 2 H+ 2 H2O
Is the equation in the net glycolysis balanced?
Not balanced chemically
On what depends the exact balance equation in the net glycolysis?
Ionization state of reactants and products
For the glucose conversion to glucose 6 phosphate is needed the hexokinase/glucokinase, what else is required?
ATP
For the fructose 6 P conversion to fructose 1,6 BP is required ATP, wich enzyme catalyzes this reaction?
Phosphofructokinase
Which processes produces ATP during the glycolysis?
1,3 BPG→ 3PG
Phosphoenolpyruvate → Pyruvate
Which enzyme catalyzes the conversion from Phosphoenolpyruvate → Pyruvate?
Pyruvate kinase
Which enzymes manages the conversion from fructose 2, 6 biphosphate to Fructose 6 phosphate?
Fructose biphosphatase 2 (FBPase2)
When does Fructose biphosphatase 2 (FBPase2) is activated?
Activated in fasting state
Which enzymes manages the conversion from Fructose 6 phosphate to fructose 2, 6 biphosphate?
Phosphofructokinase-2 (PFK 2)
When does Phosphofructokinase-2 is activated?
Activated during fed state
This enzymes are the same bifunctional enzyme whose function is reversed by phosphorylation by protein kinase A
Phosphofructokinase-2 (PFK 2) and Fructose biphosphatase 2 (FBPase2)
During the Fasting state which process is increase, Glycolysis or Gluconeogenesis
Gluconeogenesis
Who is primary increase during the fasting state?
Increase Glucagon
The increase of Glucagon during fasting state increases cAMP, after this… who is increased?
↑ protein kinase A
If the protein Kinase A is increased during fasting, which enzyme is increased and which one decreased?
Fructose biphosphatase 2 (FBPase2) is increased
Phosphofructokinase-2 (PFK 2) is decreased
Who is primary increase during the fed state?
Increase Insulin
The increase of insulin during fed state decreases cAMP, after this… who is decreased?
↓ protein kinase A
If the protein Kinase A is decreased during feeding, which enzyme is increased and which one decreased?
Fructose biphosphatase 2 (FBPase2) is decreased
Phosphofructokinase-2 (PFK 2) is increased
This mitochondrial enzyme complex links the glycolysis and TCA cycle?
Pyruvate dehydrogenase complex
When does the Pyruvate dehydrogenase complex is activated?
Active in fed state
Which is the reaction catalyzed by Pyruvate dehydrogenase complex?
pyruvate+ NAD+ CoA→ acetyl-CoA+CO2 + NADH
In the mitochondrial enzyme complex which links the glycolysis and TCA cycle, how many enzymes and cofactors it contains?
Contains 3 enzymes that require 5 cofactors
Which are the 5 cofactors in the Pyruvate dehydrogenase complex?
Pyrophosphate (B1 thiamine; TPP) FAD (B2 riboflavin) NAD (B3 NIacin) CoA (B5 pantothenate) Lipoic Acid
What happens to NAD/ NADH ratio, ADP and Ca2+ during exercise in the Pyruvate dehydrogenase complex?
They´re increased
The Pyruvate dehydrogenase complex to which complex is it similar?
α ketoglutarate dehydrogenase complex
In the TCA cycle what is the final product of α ketoglutarate
Succinyl CoA
Which elemet inhibits lipoic acid?
Arsenic
During the inhibition caused by Arsenic to lipoic acid which symptoms are common?
Vomiting, rice watter stools, garlic breath
If there is a Pyruvate dehydrogenase complex deficiency, which would be the consequences?
Causes a buildup of pyruvate that gets shunted to lactate (via LDH) and alanine (via ALT)
Which are the only purely ketogenic aminoacids?
Lysine and Leucine
Which findings are common during the Pyruvate dehydrogenase complex deficiency?
Neurologic defects, lactic acidosis, increase alanine starting in infancy
This is the treatment for Pyruvate dehydrogenase complex deficiency
Increase intake of ketogenic nutrients (high content or increase lycine and leucine)
From Glucose we can get pyruvate, but from pyruvate what do we get?
Alanine
Oxaloacetate
Acetyl CoA
Lactate
Which pyruvate product is related to Cahill cycle?
Alanine
This pyruvate product is the result of Cori cycle
Lactate
Which enzyme and cofactor helps during the pyruvate metabolic pathway in order to get Alanine?
Alanine aminotransferase (B6 as a cofactor)
What is the importance of alanine?
It carries amino groups to the liver from muscle
Which enzyme and cofactor helps during the pyruvate metabolic pathway in order to get Oxaloacetate?
Pyruvate carboxylase (biotin as cofactor)
What is the importance of Oxaloacetate?
Can replenish TCA cycle or be used in gluconeogenesis
Which enzyme and cofactor helps during the pyruvate metabolic pathway in order to get Acetyl CoA?
Pyruvate dehydrogenase (B1, B1, B3, B5, lipioc acid)
What is the importance of Pyruvate dehydrogenase?
Transition from glycolysis to the TCA cycle
Which enzyme and cofactor helps during the pyruvate metabolic pathway in order to get Lactate?
Lactic acid dehydrogenase (B3)
End of anaerobic glycolysis
Lactate
This is the step preview to entering the Kreb cycle
Pyruvate→ Acetyl Co’A
During the transition from pyruvate → Acetyl CoA in the TCA cycle, what is produce?
1 NADH and 1 CO2
Where does the Krebs cycle takes place?
Mitochondria
Which are the results from the TCA cycle?
3 NADH, 1 FADH2, 2 CO2, 1 GTP per acetyl CoA
How much ATP is needed for each acetyl CoA?
10
Who requires the same cofactors as the pyruvate dehydrogenase complex?
α ketoglutarate
Which cofactors does α ketoglutarate needs?
B1, B2, B3, B5, lipoic acid
Which is the mnemonic for the Krebs cycle?
Citrate Is Krebs Starting Substrate For Making Oxaloacetate
Which enzyme is required for Acetyl CoA to get to Citrate?
Citrate synthase
Which enzyme is required for Oxalatoacetate to get to Citrate?
Citrate synthase
Which enzymes are irreversible during Krebs cycle?
Citrate synthase
Isocitrate dehydrogenase
α KG dehydrogenase
Which are the substrates from TCA cycle?
Citrate Isocitrate α Ketoglutarate Succinyl CoA Succinate Fumarate Malate Oxaloacetate
The NADH electrons produce from glycolysis, where do they go?
Thet enter the mitochondria
How does the NADH electrons produce from glycolysis enter the mitochondria?
Via the malate aspartate or glycerol 3 phosphate shuttle
Where are transfered the FADH2 electrons in the mitochondria?
To complex II
In the mitochondria, who is transfered at lower energy the FADH2 or NADH electrons?
FADH2
What is the result of the passage of electrons in the mitochondria?
Results in the formation of proton gradient
What is the result of proton gradient coupled to oxidative phosphorylation?
Production of ATP
On what consists the complex II?
Succinate dehydrogenase
Who inhibits the complex IV in the mitochondria?
Cyanide
CO
Antimycin A inhibits this complex in the mitochondria
Complex III
Rotenone inhibits Mitochondria complex V
False Rotenone inhibits Compex I
Who inhibits Mitochondria Complex V?
Oligomycin
What is produce by Mitochondria complex I, III, IV and V?
H+
Acts as a proton ionophore, an agent that can shuttle protons (hydrogen cations) across biological membranes. It defeats the proton gradient across mitochondria and chloroplast membranes.
2,4 Dinitrophenol
By which enzyme is ATP produce?
ATP synthase
How many ATP are produce for each NADH?
2.5 ATP
By each FADH2 how many ATPs are produce?
1.5 ATP
This poisoning directly inhibit electron transport, causing a ↓ proton gradient and block of ATP synthesis
Rotenone
Cyanide
Antymicin A
CO
Directly inhibit mitochondrial ATP synthase, causing an ↑ proton gradient
Oligomycin
Why it isn´t produce any ATP by Olygomycin?
Electron transport stops
Produces heat. Increase permeability of memebrane, causing a decrease proton gradient and increase O2 consumption
2, 4 Dinitriphenol
Aspirin
Thermogenin
With the 2, 4 Dinitriphenol how is the ATP synthesis and the electron transport?
ATP synthesis stops
Electron transport continues
Which is the illicitly use for 2, 4 Dinitriphenol?
For weight loss
Which is a common secondary effect of aspirin after an overdose?
Fever
Where do we find thermogenin?
In brown fat
Which are the irrevesible enzymes during the gluconeogenesis?
Pyruvate Carboxylase
Phosphoenolpyruvate carboxykinase
Fructose 1,6 bisphosphatase
Glucose 6 phosphate
In the gluconeogenesis, where does the pyruvate→ oxaloacetate is performed?
In mitochondria
In the gluconeogenesis, which enzymes catalyzes pyruvate→ oxaloacetate?
Pyruvate carboxylase
In the gluconeogenesis, which cofactors does pyruvate carboxylase needs to catalyze pyruvate→ oxaloacetate?
Biotin
ATP
Who activates Pyruvate carboxylase?
Acetyl CoA
In the gluconeogenesis, where does the oxaloacetate → Phosphoenolpyruvate is performed?
In Cytosol
In the gluconeogenesis, which enzymes catalyzes oxaloacetate → Phosphoenolpyruvate?
Phosphoenolpyruvate carboxykinase
In the gluconeogenesis, what does Phosphoenolpyruvate carboxykinase needs to catalyze oxaloacetate → Phosphoenolpyruvate
Requires GTP
In the gluconeogenesis, where does the Fructose 1,6 BP→ Fructose 6 phosphate is performed?
In cytosol
In the gluconeogenesis, which enzymes catalyzes Fructose 1,6 BP→ Fructose 6 phosphate?
Fructose 1-6 biphosphatase
In the gluconeogenesis, which cofactors positively stimulates Fructose 1-6 biphosphatase to catalyze Fructose 1,6 BP→ Fructose 6 phosphate
Citrate
In the gluconeogenesis, which cofactors inhibits Fructose 1-6 biphosphatase to catalyze Fructose 1,6 BP→ Fructose 6 phosphate
Fructose 2,6 biphosphate
In the gluconeogenesis, where does the Glucose 6 P→ Glucose?
In Endoplasmic Reticulum
In the gluconeogenesis, which enzymes catalyzes Glucose 6 P→ Glucose?
Glucose 6 phosphatase
Primarily where does the gluconeogenesis happens? What is it purpose?
Occurs primarily in the liver, serves to mantain euglycemia during fasting.
Which other organs can we find the irrevesible enzymes of the Gluconeogenesis?
Kidney, intestinal ephithelium.
What happens if there is a deficiency of the key glucogenic enzymes?
Hypoglicemia
Why can´t the muscle participate in gluconeogenesis?
Because it lacks glucose 6 phosphatase
Which other route serves as glucose source?
Odd chain fatty acids yield 1 propionyl CoA during metabolism, which can enter the TCA cycle (as succinyl CoA) undergo gluconeogenesis
Why can´t the Even chain fatty acids produce new glucose?
Since they yield only acetyl CoA equivalents
Provides a source if NADPH from abundantly avaible glucose 6-P
HMP shunt (pentose phosphate pathway)
What is required for the reductive reactions?
NADPH
This are examples of reductive reactions that need NADH
Glutathione reduction inside RBCs, fatty acid and cholesterol biosynthesis
What else does the HMP shunt yields?
Yields ribose for nucleotide synthesis and glycolytic intermediates
Which are the distinctic phases in the pentose phosphate pathway
Oxidative and nonoxidative
Where do the oxidative and nonoxidative phases of the HMP shunt occurs?
cytoplasm
How many ATPs are produced and used during the HMP shunt?
No ATP is used or produced
These are the sites where the pentose phosphate pathway take place
Lacting mamary glands, liver, adrenal cortex (sites of fatty acid or steroid synthesis) RBCs
In the oxidative and nonoxidative reactions in the HMP shunt, Which one is irreversible?
Oxidative
In the oxidative reaction in the pentose phosphate pathway, this is the start point
Glucose 6 Phosphate
These two metabolic pathways have Glucose 6 phosphate as the start point
Glycolysis and pentose phosphate pathway
Which are the products from the oxidative phase in the HMG shunt?
CO2
2 NADPH
Ribulose 5 P
Glucose 6 P dehydrogenase is one of the main enzymes in which metabolic process?
pentose phosphate pathway
Who stimulates and who inhibits the oxidative phase in the HMG shunt?
NAPD stimulates
NADPH exces inhibits
This is the end point of the oxidative reaction, but also the start point in the nonoxidative reaction in the pentose phosphate pathway
Ribulose 5 P
Which are the final products of the nonoxidative phase with the Ribulose 5 P?
Ribose 5 P
G3P
F6P
Which enzyme is needed for Ribulose 5 P to get to the final products?
Phosphopentose isomerase transketolases
Which cofactor is required for Ribulose 5 P to get to the final products?
Requires B1
In the Respiratory burst what does it involves?
Involves the activation of the phagocyte NADPH oxidase complex
What other name does the respiratory burst receives?
Oxidative burst
During the Respiratory burst, which is the substrate for the phagocyte NADPH oxidase complex?
O2
These cells are example of phagocyte NADPH oxidase complex
Neutrophils, monocytes
What is the importance of the respiratory burst?
Plays an important role in the immune response→ rapid release of reactive oxygen species
Who plays an important role in the creation and neutralization of Reactive Oxigen Species (ROS)?
NADPH
Who gives the blue green heme containing pigment to the sputum?
Myeloperoxidase
Which disease has NADPH oxidase deficiency?
Chronic granulomatous disease (CGD)
What happens to the phagocytes of patients with Chronic Granulomatous disease (CGD)?
Phagocytes can utilizr H2O2generated by invading organism and convert it to ROS
The CGD patients are at higher risk for infection, from whom ?
Catalase + species
Which benefit Catalase + species have against phagocytes?
Catalase + species are capable of neutralizing their own H2O2, leaving phagocytes without ROS for fighting infections
Which bacterias are examples of catalase + species?
S. Aureus
Aspergillus
Can P. aeruginosa kill competing microbes? How?
Pyocyanine of P. aeruginosa functions to generate ROS to kill competing microbes
This protein inhibits microbial growth via iron chelation
Lactoferrin
Where do we find Lactoferrin?
In secretory fluids and neutrophils
What is the relationship between NADPH and glutathione?
NADPH is necessary to keep glutathione reduced
What repercussion has that NADPH reduces glutathione?
Detoxifies free radicals and peroxides
What happens to the RBC if there is a decrease in NADPH?
Leads to an hemolytic anemia due to poor RBC defence agianst oxidizing agents
Give examples of oxidizing agents that can lead to hemolytic anemia?
Fava beans, sulfonamides, primaquine, antituberculosis drugs
What else can precipitate hemolysis and it´s worst if there is a decrease of NADPH?
Infection
How does infection can lead to hemolysis?
Free radicals generated via inflamatory response can diffuse into RBCs and cause oxidative damage
If there is a Glucose 6 phosphate dehydrogenase deficiency, which would be the results?
A lack of NADPH, and with that a glutathione increased resulting in increased radicals and peroxides
Which kind of genetic disorder is Glucose 6 phosphate dehydrogenase deficiency?
X linked recessive disorder
Which is the most common human enzyme deficiency?
Glucose 6 phosphate dehydrogenase deficiency
In whom is the glucose 6 phosphate dehydrogenase deficiency more prevalent?
Among blacks
How is related the glucose 6 phosphate dehydrogenase deficiency to the malaria?
Increases malarial resistance
What is the product of the Glucose 6 phosphate after 6 phosphate dehydrogenase catalazes it?
6 phosphogluconate and NADH
Oxidized Hemoglobin precipitaed within RBCs
Heinz bodies
Result from the phagocytic removal of Heinz bodies by splenic macrophages
Bite cells
Are consider Disorders of fructose metabolism
Essential fructosuria
Fructose intolerance
Involves a defect in fructokinase
Essential fructosuria
The essential fructosuria, which kind of mode of inheritance does it follows?
Autosomal recessive
Clinically, how is consider the Essential fructosuria?
A benign, asymptomatic condition
Why is the essential fructosuria a benign asymptomatic condition?
Because fructose isn´t trapped in cells
Which would be the findings in Essential fructosuria?
Fructose in blood and urine
Which disorder of the metabolism causes less severe symptoms… Fructose or Galactose disoder?
Disorders of the fructose metabolism cause milder symptoms than analogous disorder of galactose metabolism
Which is the cause of hereditary fructose intolerance?
Hereditary deficiency of aldolase B
The fructose intolerance, which kind of mode of inheritance does it follows?
Autosomal recesive
Where is carried the fructose metabolism?
Liver
If there is a lack of aldolase B, who is accumulated?
Fructose 1 P
What happens if there is a Fructose 1 P accumulation?
Decrease in avaible phosphate
Which cycles are inhibited if there is a lack in phosphate due to Fructose 1 P accumulation?
Glycogenolysis
Gluconeogenesis
When do the symptoms present in the fructose intolerance?
Following consumption of fruit, juice or honey
How do we expect the urine dipstick be in Fructose intolerance?
Negative (test for glucose urine only)
Which are the symptoms found in Fructose intolerance
Hypoglicemia
Jaundice
Cirhosis
Vomiting
For fructose intolerance the treatment is just decrease the intake of fructose
Decrease the intake of fructose and sucrose
Which are the compounds of sucrose?
Glucose + fructose
Which are the disorders of galactose metabolism?
Galactokinase deficiency
Classic galactosemia
In order to get Galactose 1 P from Galactose which enzyme is needed?
Galactokinase
If we have a Galactokinase deficiency and still continue having galactose in our diet, Who is going to accumulate?
Galactitol
Which mode of inheritance does Galactokinase deficicency follows?
Autosomal Recessice
Which findings can be expected from Galactokinase deficicency?
Galactose appears in blood and urine, infantile cataracts
Initially how are manifested the infantile cataracts in the Galactokinase deficicency?
Failure to track objects or to develop a social smile
Which is the cause of the classic galactosemia?
Absence of Galactose 1 phosphate uridyltransferase
Which mode of inheritance does classic galactosemia follows?
Autosomal recessive
How is the damaged caused in classic galactosemia?
By Accumulation of toxic substances (including galactitol, which accumulates in the lens of the eye)
Failure to thrive, jaundice hepatomegaly, infantile caracts, intellectual disability are symptoms of which kind of metabolism disorder
Classic galactosemia
What kind of diet does the Classic galactosemia patient needs to follow?
Exclude galactose and lactose
Which are the compounds of lactose?
(galactose + glucose)
Where does the most serious defect can leads in classic galactosemia?
It can lead to PO4 depletion
The classic galactosemia which kind of infection can lead in neonates?
E. Coli Sepsis in neonates
An alternative method of trapping glucose in the cell is to convert it to its alcohol counterpart, How is named this alcohol counterpart?
Sorbitol
Which is the enzyme that catalizes the convertion from glucose to sorbitol?
Aldose reductase
Which is the substrate form by sorbitol after Sorbitol dehydrogenase catalyzes it?
Fructose
Which tissues have aldose reductase and sorbitol dehydrogense?
Liver, ovaries, and seminal vesicles have both enzymes
What happens if there is an insufficient amount of aldose reductase and sorbitol dehydrogense in some tissues?
Sorbitol accumulates, causing osmotic damage
Which symptomps are seen with sorbitol accumulation?
Cataracts, retinopàthy and peripheral neuropathy seen with chronic hyperglycemia in diabetes
Aldose reductase in which metabolic pathways is related?
Glucose → Sorbitol
Galactose → Galacitol
Which tissues just have Aldose reductase?
Schwann cells, retinam and kidneys
Where does the lactase functions to digest lactose?
On the brush border
Lactase digests lactose in which compounds?
Glucose and galactose
In what consists primary lactase deficiency?
Age dependent decline after childhood (absence of lactase persistent allele)
In which kind of people is common the lactase deficiency?
Asian, African or Native American descent
What happens in the secondary lactase deficiency?
Loss of brush border due to gastroenteritis (rotavirus), autoimmune disease
Which are the causes of Lactase deficiency?
Primary
Secondary
Congenital
What does the lactase deficency demonstrate in the stools?
↓ pH
What does the lactase deficency shows breath?
↑ Hydrogen content with lactose tolerance test
What does intestinal biopsy reveals in Lactase intolerance?
Normal mucosa in patients with lactose intolerance
Bloating, cramps, flatulence, osmotic diarrhea are the main symptomps of which metabolic disorder?
Lactase deficiency
Which is the management of Lactase deficiency?
Avoid dairy products or add lactase pills to diet; lactose free milk
Which kind of aminoacids are found in proteins?
Only L form amino acids
Which is the classification of essential aminoacids?
Glucogenic, Glucogenic/ketogenic, and ketogenic
These essential aminoacid are Glucogenic
Methionine, Valine, Histidine
These essential aminoacids are consider glucogenic/ ketogenic aminoacids
Isoleucine, phenylalanine, threonine, thypthophan
Which are examples of Ketogenic aminoacids?
Leucine, Lysine
Which are the three types of Amino acids?
Essential
Acidic
Basic
Give examples of acidic amino acids
Aspartic acid and glutamic acid
Which is the characteristic of the acidic aminoacids?
Nagatively charged at body pH
These are examples of basic amino acids
Arginine, lysine and histidine
Which of the three basic amino acids is the most basic?
Arginine
Which of the three basic amino acids has no charge at body pH?
Histidine
Which basic amino acids are required during periods of growth?
Arginine and histidine
Which basic amino acids are increased in histones? Why are they important?
Arginine and Lysine, which bind negatively charged DNA
Which amino acids need to be supplied in diet?
All essential amino acids
Why is it important the amino acid catabolism?
Results in the formation of common metabolites (pyruvate, acetyl CoA) which serve as metabolic fuels
What happens to the excess nitrogen (NH3) generated by Amino acid catabolism?
Is converted to urea and excreted by the kidneys
What is the name of the process where the excess nitrogen (NH3) is converted to urea and excreted by the kidneys?
Urea cycle
During the Urea cycle from the Starting point NH3 + CO2, which is the next step? and which enzyme is used? which is the cofactor required?
Carbamoyl phosphate is the substrate
Carbamoyl phosphate synthetase I is the enzyme
N acetylglutamate the cofactor
Where are realized the first step of the Urea cycle?
Mitochondria
Which substrate is formed thanks to Carbamoyl phosphate and Ornithine by Ornithine transcarbamylase?
Citruline
Which are the substrate of Urea cycle?
Ornithine Carbamoyl phosphate Citruline Asoartate Argininosuccinate Fumarate Arginine Urea
Who transports amonia?
Alanine and glutamate
Is the Hyperammonemia acquired or hereditary?
Both
How does Hyperammonemia can be aquired?
By liver disease
This is an example of how you get hereditary hyperammonemia
Urea cycle deficiencies
Results in excess NH4 which depletes α ketoglutarate
Hyperammonemia
Which cycle is inhibited by Hyperammonemia ?
The Excess of NH4 which depletes α ketoglutarate leads to inhibition of TCA cycle
Which diet is recomended in hypermmonemia?
Limit protein in diet
Which medicines may decrease amonia levels?
Benzoate and phenylbutyrate
How does Benzoate and phenylbutyrate decrease amonia levels?
Both bind amino acid and lead to excretion
What helps to acidify the GI tract and trap NH4 for excretion?
Lactulose
Which symptomps are seen in Amonia intoxication?
Tremor (asterixis), slurring of speech, somnolenc, vomiting, cerebral edema, blurring vision
Required cofactor for carbamoyl phosphate synthetase I?
N acetylglutamate
The absence of N acetylglutamate in which disease can it end?
Hyperammonemia
N acetylglutamate deficiency presention is identical to which other deficiency?
Carbamoyl phosphate synthetase I deficiency
How can you differentiate N acetylglutamate deficiency and Carbamoyl phosphate synthetase I deficiency?
↑ ornithine with normal urea cycle enzymes suggest hereditary N acetyl glutamate deficiency
Which is the most common urea cycle disorder?
Ornithine transcabamylase deficiency
Which mode of inheritance does Ornithine transcabamylase deficiency follows?
X linked recessive
With what does the Ornithine transcabamylase deficiency interferes in the body?
Interferes with body´s ability to eliminate ammonia
Who transports amonia?
Alanine and glutamate
Is the Hyperammonemia acquired or hereditary?
Both
How does Hyperammonemia can be aquired?
By liver disease
This is an example of how you get hereditary hyperammonemia
Urea cycle deficiencies
Results in excess NH4 which depletes α ketoglutarate
Hyperammonemia
Which cycle is inhibited by Hyperammonemia ?
The Excess of NH4 which depletes α ketoglutarate leads to inhibition of TCA cycle
Which diet is recomended in hypermmonemia?
Limit protein in diet
Which medicines may decrease amonia levels?
Benzoate and phenylbutyrate
How does Benzoate and phenylbutyrate decrease amonia levels?
Both bind amino acid and lead to excretion
What helps to acidify the GI tract and trap NH4 for excretion?
Lactulose
Which symptomps are seen in Amonia intoxication?
Tremor (asterixis), slurring of speech, somnolenc, vomiting, cerebral edema, blurring vision
Required cofactor for carbamoyl phosphate synthetase I?
N acetylglutamate
The absence of N acetylglutamate in which disease can it end?
Hyperammonemia
N acetylglutamate deficiency presention is identical to which other deficiency?
Carbamoyl phosphate synthetase I deficiency
How can you differentiate N acetylglutamate deficiency and Carbamoyl phosphate synthetase I deficiency?
↑ ornithine with normal urea cycle enzymes suggest hereditary N acetyl glutamate deficiency
Which is the most common urea cycle disorder?
Ornithine transcabamylase deficiency
Which mode of inheritance does Ornithine transcabamylase deficiency follows?
X linked recessive
With what does the Ornithine transcabamylase deficiency interferes in the body?
Interferes with body´s ability to eliminate ammonia
When is evident the ornithine transcarbamylase deficiency?
Often evident in the first few days of life, but may present with late onset
If there is an excess of carbamoyl phosphate in what is it converted?
Orotic Acid
Which pathway is orotic acid related?
Part of the pyrimidine synthesis pathway
↑ Orotic Acid in blood and urine, ↓ BUN, symptoms of hyperammonemia
Which are the findings in ornithine transcabamylase deficiency?
This finding helps to diferentiate ornithine transcabamylase deficiency and Orotic Aciduria
No megaloblastic anemia in ornithine transcabamylase deficiency
Which is the chain of derivatives from the amino acid Phenylalanine?
Phenylalanine→ Tyrosine → Dopa → Dopamine→ NE→ Epi
Which other derivative does Tyrosine has, apart from Dopa?
Thyroxine
What other derivative does Dopa has, other than Dopamine?
Melanin
The amino acid tryptophan has two derivatives, who are they?
Niacin
Serotonin
Which products can Niancin could have?
NAD+/ NADP+
Melatonin is the derivative of whom?
Serotonin
Which amino acid is the precursos of Histamine?
Histidine
This aminoacid is important in the Heme synthesis
Glycine
What is the result of Glycine after B6 works as a cofactor
Porphyrin
Glutamate can have two dericatives, who are they?
GABA
Glutathione
This three are the derivatives if Arginine
Creatinine
Ura
Nitric Oxide
Which enzyme catalyzes the reaction from Phenylalanine to tyrosine
Phenylalanine hydroxylase
If there is a deficiency in Phenylalaline hydroxylase which disease can be caused?
Phenylketonuria
Who is the precursor of Homogentisic acid?
Tyrosine
After Homogentisate oxidase catalyzes Homogentisic acid, Who is the result?
Maleylacetoacetic acid
Which disease is caused if there is a deficiency in Homogentisate oxidase?
Alkaptonuria
Which cycle is Maleylacetoacetic acid precursor?
TCA cycle
From Tyrosine to DOPA which enzyme acts?
Tyrosine hydroxylase
What is the meaning of DOPA?
Dihydroxyphenylalanine
If Melanin is a derivate of DOPE, which enzyme is affected in albinism in this conversion?
Tyrosinase
Which enzyme acts in the catalization from DOPA to Dopamine?
Dopa decarboxylase
Which medicine inhibits Dopa decarboxylase in the conversion of dopamie from DOPA?
Carbidopa
Which cofactor is needed to get Norepinephrine from Dopamine
Vitamin C
In the catecholamine synthesis, S adenosyl Methionine is needed to obtain…
Norepinephrine → Epinephrine
This suprarenal cortex product stimulates positively the conversion from Norepinephrine to Epinephrine
Cortisol
Methanephrine is the direct result of Norepinephrine or Epinephrine?
Epinephrine results in Metanephrine
Norepiephrine results in Normetanephrine
Which is the common result of Metanephrine
and Normetanephrine?
Vanillylmandelic acid
Homovanilic acid comes from?
Dopamine
Which are the causes of Phenylketonuria?
Due to ↓ phenylalanine hydroxylase or ↓ tetrahydrobiopterin cofactor
Which is consider the malignant PKU?
↓ tetrahydrobiopterin cofactor
What is increase in the urine thanks to the increase of phenylalanine?
Phenylketones in urine
Which are the findings in PKU?
Intellectual disability, growth retardation , seizures, fair skin, eczema, musty body odor
What is the treatment in PKU patients?
↓ Phenylalanine and ↑ Tyrosine in diet
What kind of inheritance pattern does PKU follows?
Autosomal recessive
Which would be the incidence of PKU?
1: 10, 000
After birth when does the neonate has to be screen in PKU?
Screened 2-3 days after birth
Why the PKU neonates are normal at birth?
Because of maternal enzyme during fetal life
Which kind of artificial sweetner does the PKU patients must avoid?
Artificial sweetner aspartame, which contains phenylalanine
This is the cause of maternal PKU?
Lack of proper dietary therapy during pregnancy
Microcephaly, intellectual disability, growth retardation, congenital heart defects are findings of?
Maternal PKU
Give the explanation of Alkaptonuria
Congenital deficiency of homogentisate oxidase in the degradative pathway of tyrosine to fumarate
This is mode of inheritance in Alkaptonuria
Autosomal recessive
Which other names doers Alkaptonuria receives?
Ochronosis
The alkaptonuria, is it a benign or malignant disease?
Benign disease
How is made the cystine?
Made of 2 cysteines connected by a disulfide bond
The homocystinuria follows this mode of inheritance
Autosomal recessive
Name the three types of homocystinuria
Cystathionine synthase deficiency ↓ Affinity of cystathionine synthase for pyridoxal phosphate Homocysteine methyltransferase (methionine synthase) deficiency
The treatment of this homocysteine type is ↓ methionine, ↑ cysteine, ↑B12 and folate in diet
Cystathionine synthase deficiency
In this kind of Homocystinuria, Which is the treatment in ↓ Affinity of cystathionine synthase for pyridoxal phosphate?
↑↑ B6 and ↑ cysteine in diet
The treatment in this Homocysteine type is just to increase Methionine in diet
Homocysteine methyltransferase (methionine synthase) deficiency
What is the result of each type of homocystinuria?
All forms result in excess homocysteine
Which findins are expected in homocystinuria?
↑↑ homocysteine in urine, intellectual disability, osteoporosis, tall statur, kyphosis, lens subluxation, thrombosis, and atherosclerosis (stroke and MI)
Methionine is the result from homocysteine but which is the enzyme and cofactors that manage it?
Homocysteine methyltransferase and B12
Cystathione synthase and vitamin B6 are required for getting Cystathinine, but Which are the substrate required to get it?
Homocysteine and Serine
Which is the product of Cystathionine?
Cysteine
Which is the explantion of cystinuria?
Hereditary defect of renal PCT and intestinal amino acid transporter for Cysteine, Ornithine, Lysine and Arginie (COLA)
Which could be the result of excess cystine in the urine?
Can lead to precipitation of hexagonal cystine stones
This is the inheritance mode of cystinuria
Autosomal recessive
How common the cystinuria?
Common 1: 7000
Which is the diagnostic tool of cystinuria?
Urinary cyanide nitroprusside test is diagnostic
Which is the treatment for cystinuria?
Urinary alkalinization and chekating agents increase solubility of cystine stones
Good hydration
Which is the mnemonic of glycogen storage disease types?
Very Poor Carbohydrate Metabolism
How is made the cystine?
Made of 2 cysteines connected by a disulfide bond
Which is the principle of the maple syrup urine disease?
Blocked degradation of branched amino acids due to ↓ α Ketoacid dehydrogenase (B1)
What does the Blocked degradation of branched amino acids due to ↓ α Ketoacid dehydrogenase (B1) causes?
Causes ↑ α Ketoacids in blood, especially those of leucine
Clinically what does the maple syrup urine disease causes?
Severe CNS defects, intellectual disability and death
The maple syrup urine disease is a autosomal dominant or autosomal recessive disease?
Autosomal Recessive
Why does the maple syrup urine disease has that name?
Because the urine smells like maple syrup/burnt sugar
Which are the three branched aminoacids?
Isoleucine
Leucine
Valine
Which are the restriction in diet in the Maple syrup urine disease? and what would you supplement?
Restriction of Leucine, isoleucine and valine in diet
Supplementation of Thiamine
In the glycogen structure how are the branches and linkage composed?
Branches have α- (1,6) bonds; linkages have α-(1,4) bonds
These tissues have high reserves of glycogen
Skeletal muscle
Hepatocytes
In the skeletal muscle the glycogen is rapidly metabolized, so which is the process of glycogenolysis
Glycogen → glucose 1 phosphate → Glucose 6 P
What realationship does the Glycogen has with the liver?
Glycogen is stored and undergoes glycogenolysis to maintain blood sugar at appropiate levels
Which is the process of Glycogenoslysis?
Glycogen phosphorylase cleaves glucose 1 P residues off branched glycogen until four remain befora a branch point. Then 4 α-D- glucanotransferase moves three glucose 1 Ps from the branch to the linkage. Then α- 1,6 glucosidase cleaves off the last glucose 1 P on the branch
During the glycogenolysis which are consider debranching enzymes?
4 α-D- glucanotransferase
α- 1,6 glucosidase
A small amount of glycogen is degraded in lysosomes by which enzyme?
α- 1,4 glucosidase (Acid Maltase)
How many Glycogen storage diseases exist?
12 types
Which are the four most common types of Glycogen storage disease?
Von Gierke disease (Type I) Pompe disease (Type II) Cori disease (Type III) McArdle disease (Type V)
Which is the only X Recessive disease in the Sphingolipidoses?
Fabry disease, The other are Autosomal Recessive
What kind of inheritance pattern follows all the glycogen storage disease?
Autosomal recessive
What are the Gaucher cells?
Lipid laden macrophages resembling crumpled tissue paper
Which enzyme is deficient in Von Gierke disease?
Glucose 6 phosphate
Which would be the management of Von Gierke disease?
Frequent oral glucose / cornstarch; avoidance if fructose and galactose
This glycogen storage disease has Lysosomal α 1, 4 glucosidase (acid maltase) deficiency
Pompe disease (Type II)
Which findings are common in Pompe disease?
Cardiomyopathy and systemic findings leading to early death
This is a milder form type I Glycogen storage disease but with normal blood lactate
Cori disease (Type III)
How is the gluconeogenesis in Cori disease?
Is intact
Which enzyme is related to Cori disease?
α 1,6 glucosidase
In which tissue is McArdle disease (Type V) more related? and with which enzyme?
Skeletal muscle glycogen phosphorylase (myophosphorilase)
How is the glycogen in the muscle in McArdle disease?
↑ glycogen in muscle, but cannot break it down
So… if there is ↑ glycogen in muscle, but cannot be broken down in McArdle disease, which are the clinical manifestations during strenous excercise?
Painful muscle cramps, myoglobinuria (red urine)
Which other anormalities can be found in McArdle disease?
Arrythmia from electrolyte abnormalities
Name the two type of Lysosomal storage disease
Sphingolipidoses and Mucopolysaccharidoses
Which are the shingolipidoses seen in the Lysosomal storage disease?
Fabry disease Gaucher disease Niemann Pick disease Tay Sachs disease Krabbe disease Metachromatic leukodystrophy
The findings in this sphingolipidoses is peripheral neuropathy of hands/feet, angiokeratomas, cardivascular/renal disease
Fabry disease
Which enzyme is deficient and which substrate is accumulated in Fabry disease?
α galactosidase A deficiency
Ceramide trihexiside is accumulated
Which is the only X Recessive disease in the Sphingolipidoses?
Fabry disease
This is the most common lysosomal storage disease and is part of the sphingolipidoses
Gaucher disease
What are the Gaucher cells?
Lipid laden macrophages resembling crumpled tissue paper
These are the posible findings in Gaucher disease
Hepatosplenomegaly, pancytopenia, aseptic necrosis of Femur, bone crises, Gaucher cells
Which enzyme is deficient in Gaucher disease, which also is the treatment…
Glucocerebrosidase (β- glucosidase)
In Gaucher disease if Glucocerebrosidase is the deficent enzyme… Who is the accumulated substrate?
Glucocerebroside
Progressive neurodegeneration, hepatosplenomegaly, cherry red spot on macula, and foam cells… which lysosomal storage disease is?
Niemann Pick disease
What are the foam cells?
Lipid laden macrophages seen in Niemman Pick disease
Sphingomyelinase is the deficient enzyme and sphingomyelin the accumulated substrate
Niemann Pick disease
Which sphingolipidose disease is clinically similar to Niemann Pick?
Tay Sachs disease
Clinically which are the similitudes and difference between Niemman Pick and Tay-Sachs disease?
Similitudes is the progressive neurodegeneration, developmental delay, cherry red spot on macula
Difference, on Tay Sachs there is no hepatosplenomegaly (vs Niemman Pick)
Which is the accumulated substrate in Tay Sachs disease?
GM2 ganglioside
Hexoaminidase A is the deficient enzyme in this lysosomal storage disease
Tay Sachs disease
So… if there is a Carnitine deficiency which would be the expected findings?
Causes weakness, hypotonia, and hypoketotic hypoglicemia
This sphingolipidose disease has two accumulated substrates due to Galactocerebrosidase deficiency
Krabbe disease
Which are the two accumulated substrates in Krabe disease?
Galactocerebroside, psychosine
Peripheral neuropathy, developmental delay, optic atrophy are characteristics of this lysosomal storage disease
Krabbe disease
How are the cells in Krabbe disease?
Globoid cells
These findings are seen in Metachromatic leukodystrophy
Central and peripheral demyelination with ataxia, dementia
Arylsulfatase A is the deficient enzyme on this sphingolipidose disease
Metachromatic leukodystrophy
If Arylsulfatase A is the deficient enzyme on Metachromatic leukodystrophy, which is the accumulated substrate
Cerebroside sulfate
Hurler and Hunter syndrome what kind of Lysosomal storage diease are they consider?
Mucopolysaccharidoses
On this Mucopolysaccharidose disease Heparan sulfate and dermatan sulfate are the substrates accumulated but the deficient enzyme is α L iduronidase
Hurler syndrome
Which findings are common in Hurler syndrome?
Developmental delay, gargolysm, airway obstruction, corneal clouding, hepatosplenomegaly
Which are the accumulated substrates in both Hurler and Hunter syndrome?
Dermatan sulfate and heparan sulfate
Clinically how are diffent Hurler and Hunter syndrome?
Hunter is a mild Hurler + aggressive behavior, no croneal clouding in Hunter disease
This is the deficient enzyme in Hunter disease
Iduronate sulfatase
Genetically which difference do Hunter and Hurler disease have?
Hunter syndrome is X linked recessive
Hurler syndrome is Autosomal recessive
Which lysosomal storage diseases have an increased incidence in Askenazi Jews?
Tay Sachs, Niemann Pick and some forms of Gaucher disease
What does the long chain fatty acid degradation requires?
Carnitine - deoendent transport into the mitochondrial matrix
Is β hydroxybutyrate detected in urine test for ketones?
No, is not detected
So… if therer is a Carnitine which would be the expected findings?
Causes weakness, hypotonia, and hypoketotic hypoglicemia
Who is increased and who is descreased during the Acyl CoA dehydrogenase deficiency?
↑ dicarboxylic acids
↓ glucose and ketones
What role does Acetyl CoA plays with pyruvate carboxylase?
Acetyl CoA is + allosteric regulator of pyruvate carboxylase in gluconeogenesis
Which is the repercussion if ↓ Acetyl CoA?
↓ Fasting Glucose
Which substrate is the beginning for the Fatty acid synthesis?
Citrate
Where do we find citrate?
Mitochondria matrix
Where does the ATP citrate lyase catalyzes citrate in order to have Acetyl CoA?
Cell cytoplasm
How many Carbons does palmitate has?
16 C
Which are the results of the degradation of Fatty acis?
Ketone bodies
TCA cycle
Fatty acids and aminoacids where are they metabolized?
In the liver
Which are metabolized products of Fatty acids and aminoacids?
Acetoacetate and β hydroxybutyrate
Which tissues use Acetoacetate and β hydroxybutyrate?
Muscle and brain
Which metabolite is depleted in prolonged starvation and diabetic ketoacidosis?
Oxaloacetate
During which metabolic process is oxaloacetate depleted in prolonged starvation and diabetic Ketoacidosis?
Gluconeogenesis
What happens to oxaloacetate in alcoholism?
Excess NADH shunts oxaloacetate to malate
If there is a build up of Acetyl CoA during Prolonged starvation, diabetic ketoacidosis and alcoholism, what is the result?
Acetyl CoA shunts glucose and FFA toward the production of ketone bodies
If there is an excess of Ketone bodies, how is it clinically manifested?
Smells like acetone (fruit odor)
Is β hydroxybutyrate detected in urine test for ketones?
No, is not detected
How many calories per gram does the protein or carbohydrates give?
1g protein or carbohydrate= 4 kcal
1 gram of Fat how many calories does is gives?
9 kcal per 1 g fat
These calories you get per 1 g of alcohol
1 g alcohol= 7 kcal
During excercise the percentage of maximal energy at the begining is 100% but decreases rapidly, which is the first source of energy used that is burned in 2 seconds?
Stored ATP
This metabolism manages % of maximal energy for the largest periods
Aerobic metabolism
During fasting and starvation which are the priorities?
Are to supply sufficient glucose to the brain and RBCs and to preserve proteins
During fed state (after a meal) which metabolic states are present?
Glycolisis and aerobic respiration
During fed state (after a meal) what happens to insulin?
Insulin stimulates storage of lypids, protein and glycogen
These are the three main metabolic pathways that occur during Fasting (between meals)
Hepatic glycogneolysis
Hepatic gluconeogenesis and adipose release of FFA
Which is the major metabolic event that happens in Fasting?
Hepatic glycogneolysis
These are the minor metabolic events that happens in Fasting?
Hepatic gluconeogenesis and adipose release of FFA
During fasting, they stimulate use of fuel reserves
Glucagon
Adrenaline
During the 1-3 day of starvation, how are the blood glucose levels mantained?
Hepatic glycogenolysis
Adipose release of FFA
Muscle and liver, which shift fuel use from glucose to FFA
Hepatic gluconeogenesis from peripheral tissue lactate and alanine, and from adipose tissue glycerol and propionyl CoA
Which are the only triacylglycerol components that contribute to gluconeogenesis?
From odd chain FFA
After starvation in how many days the glycogen reserves are depleted?
After day 1
Can the RBCs use ketones?
No, because they lack mitochondria
If you were to last 8 weeks of starvation, in which order the source of energy will be depleated?
Carbohydrates depleted in less than 3 days
Fat in 8 weeks
Protein the 8 weeks and more, Vital protein degradation
After day 3 of starvation which is the next main source of energy for the brain?
Adipose stores- Ketones bodies become the main source of energy to the brain
After the ketones bodies are depleted during starvation, what is next?
Vital protein degradation accelerates , leading to organ failure and death
During starvation after day 3 what determines the survival time?
Amount of excess stores
In the cholesterol synthesis which enzyme converts HMG- CoA to mevalonate?
HMG- CoA reductase
Who induces HMG CoA reductase in the cholesterol synthesis?
Insulin
Who esterifies 2/3 of plasma cholesterol?
Lecithin-cholesterol acyltransferase (LCAT)
Which is the effect of statins?
Competitively and reversibly inhibit HMG- CoA reductase
Who manages the degradation of dietary triglycerides in the small intestine?
Pancreatic lipase
What is the function of Lipoprotein lipase (LPL)?
Degradation of Triglycerides circulating in chylomicrons and VLDLs
Where can we find Lipoprotein lipase?
Found on vascular endothelial surface
Its function is the degradation of Triglycerides remaining in IDL
Hepatic Triglyceride Lipase (HL)
Which is the effect of Hormone sensitive lipase?
Degradation of TG stored in adipocytes
Catalyzes esterification of cholesterol
Lecitin Cholesterol Acyl Transferase (LCAT)
Who mediates transfer of cholesterol esters to other lipoprotein particles?
Cholesterol ester transfer protein (CETP)
Which organs produce Nascent HDL
Liver and intestine
Which enzyme is required for nascent HDL to become mature HDL?
LCAT- Lecitin Cholesterol Acyl Transferase
From Mature HDL which enzyme is required to form the transfer cholesterol esters to VLDL, IDL, LDL?
CETP- Cholesterol ester transfer protein
Proteins that bind lipids to form lipoproteins, they transport the lipids through the lymphatic and circulatory system
Apolipoprotein
Which apolipoprotein mediates remnant uptake?
Apo E
Where can we find ApoE?
In every kind of lipoprotein except LDL
What is the function of Apo A I?
Activates LCAT
This apolipoprotein is just found in Chylomicron and HDL
Apo A I
It´s consider a Lipoprotein lipase cofactor
Apo C II
Where do we find Apo C II?
Chylomicron, VLDL and HDL
Found in Chylomicrons and chylomicrons remnant and mediates chylomicron secretion
Apo B 48
This Apoliporpotein binds LDL receptor
Apo B 100
These are the lipoproteins where we can find Apo B 100
VLDL, IDL, LDL
Which is the composition of Lipoproteins?
Cholesterol
Triglycerides
Phospholipids
Which lipoprotein carry most cholesterol?
HDL and LDL
Which is the direction that LDL transports cholesterol?
From liver to Tissues
This is the direction that HDL transports cholesterol
Periphery to Liver
What is the work for chylomicrons related to the triglycerides?
Delivers dietary triglycerides to peripheral tissue
This lipoprotein delivers cholesterol to liver?
Chylomicron remnants
This kind of chylomicron is mostly depleted of their triacylglycerols
Chylomicron remnants
Who secretes chylomicrons?
Intestinal epithelial cells
DElivers hepatic triglycerides to peripheral tissue
VLDL
Where is secreted the VLDL?
In the liver
Formed in the degradation of VLDL
IDL
Which is the function of IDL?
Delivers Triglycerides and cholesterol to liver
How does LDL is formed?
Formed by hepatic lipase modification of IDL in the peripheral tissue
Delivers hepatic cholesterol to peripheral tissues
LDL
How does the target cells take up the LDL?
Via receptor mediated endocytosis
Which is the function of HDL?
Mediates reverse cholesterol transport from periphery to liver
Acts as a repository for apoC and apoE (which are needed for chylomicron and VLDL metabolism)
HDL
Who secretes HDL?
Liver and intestine
Which is the relationship between alcohol and HDL?
Alcohol increases HDL synthesis
In this familial dyslipidemia type I, Who is increased in the blood level?
Chylomicrons, Tryglicerides, cholesterol
Which other name does the Familial dyslipidemia type I receives?
Hyperchylomicronemia
What kind of mode of inheritance is seen in Familial dyslipidemia type I?
Autosomal recessive
What is the problem in Familial dyslipidemia Hyperchylomicronemia?
Lipoprotein lipase deficiency or altered apolipoprotein C II
Which can be the consequences of Familial dyslipidemia type 1?
Pancreatitis , hepatosplenomegaly, and eruptive/ pruritic xanthomas
How is the risk of atherosclerosis in Familial dyslipidemia type 1?
No increased risk for atherosclerosis
In this kind of familial Dyslipidemia the LDL receptors are abscent or defective
Familial dyslipidemia type IIa
Familial hypercholesterolemia also knowns as?
Familial dyslipidemia type IIa
What is increased in blood in the Familial hypercholesterolemia?
LDL and cholesterol
This is the inheritance mode of Familial dyslipidemia type IIa
Autosomal Dominant
Which is the incidence of Familial hypercholesterolemia heterozygote?
1: 500
Which are the expected levels of cholesterol seen in an heterozygote Familial hypercholesterolemia patient?
300 mg/ dL
The homozygotes Familial hypercholesterolemia patients are very rare, but which levels of cholesterol would you expect to see?
700 mg/ dL
How is the risk of atherosclerosis in Familial dyslipidemia type IIa?
Acelerated atherosclerosis (may have MI before 20)
Which clinical findings can be seen in Familial dyslipidemia type IIa?
Tendon (Achiles) xanthomas and corneal arcus
In this familial dyslipidemia, VLDL and triglycerides are increased in blood levels
Type IV or hypertriglyceridemia
Which is the cause of Familial hypertriglyceridemia?
Hepatic overproduction of VLDL
Familial dyslipidemia type IV Is it Autosomal Dominant or Autosomal recessive?
Autosomal dominant
Which is the possible finding in Familial hypertriglyceridemia?
Pancreatitis
