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Noorda FOM > Module 5-6 Review ChatGPT > Flashcards

Module 5-6 Review ChatGPT Flashcards

1
Q

What are the primary fuel sources in myocytes, neurons, and erythrocytes during a keto diet

A

Fatty acids in myocytes, ketone bodies in neurons, and glucose in erythrocytes

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2
Q

What is the primary fuel used by the brain during prolonged fasting

A

Ketone bodies

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3
Q

What are the 4 main promoting and 2 inhibitory effects of insulin in the fed state

A

Glucose uptake, glycogen synthesis, lipogenesis, and protein synthesis
Gluconeogenesis and glycogenolysis

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4
Q

What triggers glycogenolysis and gluconeogenesis during fasting

A

The release of glucagon and epinephrine

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5
Q

What is the role of glucagon during prolonged fasting

A

Lipolysis
Ketogenesis
Gluconeogenesis

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6
Q

What are the main differences between saturated and unsaturated fats

A

Saturated fats have no double bonds and are typically solid at room temperature, while unsaturated fats have one or more double bonds and are typically liquid

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7
Q

What promoting (3) and inhibitory (1) effects does cortisol have on metabolism

A

Gluconeogenesis, proteolysis, and lipolysis
Glucose uptake in peripheral tissues

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8
Q

What promoting (2) and inhibitory (1) roles does epinephrine play in fuel mobilization

A

Rapidly mobilizes energy by increasing glycogenolysis and lipolysis
Insulin secretion

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9
Q

What is the significance of malonyl-CoA in fatty acid metabolism

A

Malonyl-CoA inhibits carnitine palmitoyltransferase I (CPT I), preventing fatty acid oxidation

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10
Q

What is the function of the pyruvate dehydrogenase complex

A

The pyruvate dehydrogenase complex converts pyruvate to acetyl-CoA, linking glycolysis to the TCA cycle

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11
Q

What effect does arsenic have on pyruvate dehydrogenase

A

Arsenic inhibits the pyruvate dehydrogenase complex by binding to dihydrolipoamide, leading to reduced activity and lactic acidosis

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12
Q

What is the result of a deficiency in glucose-6-phosphate dehydrogenase (G6PD)

A

G6PD deficiency leads to hemolytic anemia, especially under oxidative stress, due to impaired NADPH production

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13
Q

What are the key points to remember about the TCA cycle

A

The TCA cycle generates NADH and FADH2 for the electron transport chain, produces GTP/ATP, and is crucial for energy production

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14
Q

What are the effects of electron transport chain (ETC) uncoupling

A

ETC uncoupling dissipates the proton gradient as heat, reducing ATP production and increasing thermogenesis

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15
Q

What are the key inhibitors of Complex I in the ETC

A

Rotenone and Amytal

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16
Q

What are the key enzymes that circumvent gluconeogenesis

A

Pyruvate carboxylase, PEPCK, fructose-1,6-bisphosphatase, and glucose-6-phosphatase

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17
Q

What is the significance of fructose 2,6-bisphosphate in metabolism

A

Fructose 2,6-bisphosphate regulates glycolysis and gluconeogenesis, activated by insulin and inhibited by glucagon

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18
Q

What is the role of insulin in glycogen metabolism

A

Insulin stimulates glycogen synthesis and inhibits glycogenolysis

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19
Q

What are the primary effects of glucagon and epinephrine on glycogen metabolism

A

Both hormones stimulate glycogenolysis and inhibit glycogen synthesis

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20
Q

What is the role of fatty acid synthase

A

Fatty acid synthase catalyzes the synthesis of fatty acids from acetyl-CoA and malonyl-CoA in the cytoplasm

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21
Q

What is the impact of a deficiency in medium-chain acyl-CoA dehydrogenase (MCAD)

A

MCAD deficiency leads to hypoglycemia and the accumulation of medium-chain fatty acids during fasting or illness

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22
Q

What enzyme is deficient in phenylketonuria (PKU)

A

Phenylalanine hydroxylase

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23
Q

What are the symptoms of maple syrup urine disease (MSUD)

A

Sweet-smelling urine, lethargy, poor feeding, vomiting, and developmental delay

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24
Q

What causes hyperammonemia in urea cycle disorders

A

Deficiencies in enzymes like ornithine transcarbamylase (OTC) or carbamoyl phosphate synthetase (CPS) lead to the accumulation of ammonia

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25
Q

What is the function of carbamoyl phosphate synthetase I (CPS I) in the urea cycle

A

CPS I catalyzes the formation of carbamoyl phosphate from ammonia and bicarbonate, the first step in the urea cycle

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26
Q

What are the clinical features of ornithine transcarbamylase (OTC) deficiency

A

Hyperammonemia, orotic aciduria, lethargy, and cerebral edema

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27
Q

What is the role of lipoprotein lipase (LPL) in lipid metabolism

A

LPL hydrolyzes triglycerides in chylomicrons and VLDL into free fatty acids and glycerol, facilitating their uptake by tissues

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28
Q

What is the significance of ApoB-100 in lipoprotein metabolism

A

ApoB-100 is essential for the synthesis and clearance of VLDL, IDL, and LDL

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29
Q

What are the clinical features of familial hypercholesterolemia

A

Elevated LDL cholesterol, tendon xanthomas, and an increased risk of atherosclerosis

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30
Q

What is the impact of statins on cholesterol synthesis

A

Statins inhibit HMG-CoA reductase, reducing cholesterol synthesis and increasing LDL clearance from the bloodstream

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31
Q

What are the consequences of uncoupling protein (UCP) activity

A

UCPs dissipate the proton gradient in mitochondria, leading to heat generation instead of ATP production

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32
Q

What is the main source of energy during the fed state

A

Glucose is the main source of energy during the fed state

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33
Q

What are the key metabolic pathways activated during the fed state

A

Glycolysis, glycogenesis, and lipogenesis are activated during the fed state

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34
Q

What is the role of insulin in the fed state

A

Insulin promotes glucose uptake, glycogen synthesis, and fat storage, while inhibiting gluconeogenesis and glycogenolysis

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35
Q

How does the liver respond to insulin during the fed state

A

The liver increases glycogen synthesis and decreases glucose production through gluconeogenesis

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36
Q

What is the primary function of the pentose phosphate pathway

A

The pentose phosphate pathway generates NADPH and ribose-5-phosphate for nucleotide synthesis and reductive biosynthesis

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37
Q

What are the key enzymes of the pentose phosphate pathway

A

Glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase are key enzymes of the pentose phosphate pathway

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38
Q

What happens during the oxidative phase of the pentose phosphate pathway

A

NADPH is generated, which is essential for fatty acid synthesis and maintaining reduced glutathione levels

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39
Q

What is the role of NADPH in red blood cells

A

NADPH is crucial for maintaining reduced glutathione levels, which protect red blood cells from oxidative damage

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40
Q

What triggers the non-oxidative phase of the pentose phosphate pathway

A

The non-oxidative phase is triggered when the cell needs ribose-5-phosphate for nucleotide synthesis

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41
Q

What is the impact of a deficiency in glucose-6-phosphate dehydrogenase (G6PD)

A

G6PD deficiency leads to reduced NADPH production, making red blood cells more susceptible to oxidative stress and hemolysis

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42
Q

What is the role of fructose-2,6-bisphosphate in glycolysis

A

Fructose-2,6-bisphosphate activates phosphofructokinase-1 (PFK-1), enhancing glycolysis

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43
Q

How is fructose-2,6-bisphosphate regulated

A

Fructose-2,6-bisphosphate levels are regulated by insulin (which increases it) and glucagon (which decreases it)

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44
Q

What is the function of pyruvate dehydrogenase (PDH) in energy metabolism

A

PDH converts pyruvate to acetyl-CoA, linking glycolysis to the TCA cycle

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45
Q

What regulates pyruvate dehydrogenase activity

A

PDH is activated by ADP and inhibited by ATP, NADH, and acetyl-CoA

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46
Q

What is the role of the TCA cycle in cellular respiration

A

The TCA cycle generates NADH and FADH2, which are used in the electron transport chain to produce ATP

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47
Q

What are the key products of one turn of the TCA cycle

A

One turn of the TCA cycle produces 3 NADH, 1 FADH2, 1 GTP (or ATP), and 2 CO2 molecules

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48
Q

What is the importance of alpha-ketoglutarate in the TCA cycle

A

Alpha-ketoglutarate is a key intermediate that can be used for amino acid synthesis and energy production

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49
Q

What enzyme converts succinate to fumarate in the TCA cycle

A

Succinate dehydrogenase converts succinate to fumarate, and it is also part of Complex II in the electron transport chain

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50
Q

What is the role of citrate in metabolism

A

Citrate can be used in the TCA cycle, or transported to the cytoplasm for fatty acid and cholesterol synthesis

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51
Q

What is the significance of the malate-aspartate shuttle

A

The malate-aspartate shuttle transfers reducing equivalents (NADH) from the cytoplasm into the mitochondria for ATP production

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52
Q

What is the function of the electron transport chain (ETC)

A

The ETC transfers electrons from NADH and FADH2 to oxygen, driving the synthesis of ATP through oxidative phosphorylation

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53
Q

What is the role of Complex IV in the electron transport chain

A

Complex IV (cytochrome c oxidase) transfers electrons to oxygen, the final electron acceptor, forming water
Pumps protons

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54
Q

What happens during oxidative phosphorylation

A

During oxidative phosphorylation, the energy from electron transfer in the ETC is used to pump protons across the mitochondrial membrane, creating a gradient that drives ATP synthesis

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55
Q

What are the effects of ETC uncoupling on cellular metabolism

A

ETC uncoupling dissipates the proton gradient as heat, reducing ATP production and increasing thermogenesis

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56
Q

What is the function of ATP synthase in mitochondria

A

ATP synthase uses the proton gradient generated by the ETC to convert ADP and inorganic phosphate into ATP

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57
Q

What are the consequences of a deficiency in pyruvate dehydrogenase (PDH)

A

PDH deficiency leads to lactic acidosis, neurodevelopmental delay, and decreased energy production

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58
Q

What role does the enzyme hexokinase play in glycolysis

A

Hexokinase phosphorylates glucose to form glucose-6-phosphate, the first step in glycolysis

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59
Q

What is the function of phosphofructokinase-1 (PFK-1) in glycolysis

A

PFK-1 is the rate-limiting enzyme in glycolysis, converting fructose-6-phosphate to fructose-1,6-bisphosphate

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60
Q

What activates and inhibits phosphofructokinase-1 (PFK-1)

A

PFK-1 is activated by AMP and fructose-2,6-bisphosphate and inhibited by ATP and citrate

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61
Q

What is the role of pyruvate kinase in glycolysis

A

Pyruvate kinase catalyzes the final step in glycolysis, converting phosphoenolpyruvate (PEP) to pyruvate and generating ATP

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62
Q

What are the key regulatory enzymes of gluconeogenesis

A

Pyruvate carboxylase, PEPCK, fructose-1,6-bisphosphatase, and glucose-6-phosphatase are key enzymes in gluconeogenesis

63
Q

What is the function of glucose-6-phosphatase in gluconeogenesis

A

Glucose-6-phosphatase converts glucose-6-phosphate to glucose, allowing it to be released into the bloodstream

64
Q

What are the effects of insulin on gluconeogenesis

A

Insulin inhibits gluconeogenesis by decreasing the expression of key gluconeogenic enzymes

65
Q

What role does glucagon play in gluconeogenesis

A

Glucagon promotes gluconeogenesis by increasing the expression of enzymes like PEPCK and glucose-6-phosphatase

66
Q

What is the role of acetyl-CoA in fatty acid synthesis

A

Acetyl-CoA provides the two-carbon units for fatty acid synthesis, which occurs in the cytoplasm

67
Q

What enzyme is responsible for the synthesis of malonyl-CoA

A

Acetyl-CoA carboxylase catalyzes the formation of malonyl-CoA from acetyl-CoA

68
Q

What is the function of fatty acid synthase

A

Fatty acid synthase catalyzes the synthesis of palmitate (a 16-carbon saturated fatty acid) from acetyl-CoA and malonyl-CoA

69
Q

What is the impact of insulin on fatty acid synthesis

A

Insulin promotes fatty acid synthesis by activating acetyl-CoA carboxylase and increasing the availability of glucose for lipogenesis

70
Q

What happens to fatty acids during beta-oxidation

A

During beta-oxidation, fatty acids are broken down in the mitochondria to produce acetyl-CoA, NADH, and FADH2

71
Q

What regulates the rate of beta-oxidation in the mitochondria

A

The rate of beta-oxidation is regulated by the availability of fatty acids and the activity of carnitine palmitoyltransferase I (CPT I)

72
Q

What is the role of carnitine in fatty acid metabolism

A

Carnitine transports long-chain fatty acids into the mitochondria for beta-oxidation

73
Q

What is the function of hormone-sensitive lipase (HSL)

A

HSL hydrolyzes stored triglycerides in adipose tissue into free fatty acids and glycerol, which are released into the bloodstream

74
Q

What triggers the activation of hormone-sensitive lipase (HSL)

A

HSL is activated by epinephrine and glucagon during fasting or stress, leading to the mobilization of stored fats

75
Q

What is the role of ketone bodies during fasting

A

Ketone bodies provide an alternative energy source, particularly for the brain, during prolonged fasting

76
Q

What are the three main ketone bodies produced during ketogenesis

A

The three main ketone bodies are acetoacetate, beta-hydroxybutyrate, and acetone

77
Q

What happens to ketone bodies during prolonged fasting

A

During prolonged fasting, ketone bodies accumulate and are used by the brain and other tissues for energy, sparing glucose

78
Q

What is the impact of a deficiency in medium-chain acyl-CoA dehydrogenase (MCAD)

A

MCAD deficiency impairs fatty acid oxidation, leading to hypoglycemia and the accumulation of medium-chain fatty acids

79
Q

What is the role of the urea cycle in nitrogen metabolism

A

The urea cycle converts toxic ammonia into urea, which is then excreted in the urine

80
Q

What enzyme catalyzes the first step of the urea cycle

A

Carbamoyl phosphate synthetase I (CPS I) catalyzes the first step of the urea cycle, forming carbamoyl phosphate from ammonia and bicarbonate

81
Q

What are the symptoms of a urea cycle disorder

A

Symptoms include hyperammonemia, lethargy, vomiting, seizures, and, if untreated, can lead to coma or death

82
Q

What is the significance of N-acetylglutamate in the urea cycle

A

N-acetylglutamate is an allosteric activator of carbamoyl phosphate synthetase I (CPS I), the first enzyme in the urea cycle

83
Q

What is the effect of a deficiency in ornithine transcarbamylase (OTC)

A

OTC deficiency leads to hyperammonemia and elevated orotic acid levels, causing neurological damage and developmental delays

84
Q

What is the role of alanine in the transport of nitrogen

A

Alanine transports nitrogen from muscle tissue to the liver, where it is converted to urea for excretion

85
Q

What happens to amino acids during prolonged fasting

A

During prolonged fasting, amino acids are released from muscle protein and used for gluconeogenesis and energy production

86
Q

What is the function of glutamine in nitrogen metabolism

A

Glutamine carries ammonia from peripheral tissues to the liver or kidneys for excretion as urea or ammonium

87
Q

What is the significance of the Cori cycle in metabolism

A

The Cori cycle allows lactate produced by anaerobic glycolysis in muscles to be converted back to glucose in the liver

88
Q

What is the role of phenylalanine hydroxylase in amino acid metabolism

A

Phenylalanine hydroxylase converts phenylalanine to tyrosine, a precursor for neurotransmitters and melanin

89
Q

What is the consequence of a deficiency in phenylalanine hydroxylase

A

A deficiency in phenylalanine hydroxylase leads to phenylketonuria (PKU), causing the accumulation of phenylalanine and resulting in intellectual disability if untreated

90
Q

What are the key symptoms of phenylketonuria (PKU)

A

Symptoms of PKU include intellectual disability, musty body odor, fair skin, eczema, and seizures

91
Q

What is the treatment for phenylketonuria (PKU)

A

Treatment for PKU involves a low-phenylalanine diet and supplementation with tyrosine

92
Q

What enzyme is deficient in maple syrup urine disease

A

Maple syrup urine disease is caused by a deficiency in the branched-chain alpha-keto acid dehydrogenase complex

93
Q

What are the symptoms of maple syrup urine disease

A

Symptoms include sweet-smelling urine, poor feeding, vomiting, lethargy, and, in severe cases, neurological damage

94
Q

What is the role of vitamin B6 in amino acid metabolism

A

Vitamin B6 (pyridoxine) acts as a cofactor for transaminases and other enzymes involved in amino acid metabolism

95
Q

What enzyme deficiency causes homocystinuria

A

Homocystinuria is often caused by a deficiency in cystathionine beta-synthase

96
Q

What are the clinical features of homocystinuria

A

Homocystinuria is characterized by marfanoid habitus, lens dislocation, thromboembolism, and intellectual disability

97
Q

What is the difference between homocystinuria and Marfan syndrome

A

Homocystinuria features downward lens dislocation and increased risk of thrombosis, while Marfan syndrome features upward lens dislocation and aortic root dilation

98
Q

What enzyme deficiency leads to alkaptonuria

A

Alkaptonuria is caused by a deficiency in homogentisate oxidase

99
Q

What are the key symptoms of alkaptonuria

A

Symptoms of alkaptonuria include dark urine, ochronosis (bluish-black pigmentation of connective tissues), and arthritis

100
Q

What is the role of branched-chain amino acids in metabolism

A

Branched-chain amino acids (valine, leucine, isoleucine) are important for protein synthesis and can be used as energy sources

101
Q

What is the treatment approach for maple syrup urine disease

A

Treatment involves dietary restriction of branched-chain amino acids and supplementation with thiamine (vitamin B1)

102
Q

What enzyme deficiency causes orotic aciduria

A

Orotic aciduria is caused by a deficiency in uridine monophosphate synthase (UMPS)

103
Q

What distinguishes orotic aciduria from OTC deficiency

A

Orotic aciduria lacks hyperammonemia, while OTC deficiency is associated with elevated orotic acid and hyperammonemia

104
Q

What are the treatment options for homocystinuria

A

Treatment includes a low-methionine diet, high-dose vitamin B6, and, if necessary, betaine to reduce homocysteine levels

105
Q

What is the function of lipoprotein lipase (LPL)

A

Lipoprotein lipase hydrolyzes triglycerides in chylomicrons and VLDL into free fatty acids and glycerol, facilitating their uptake by tissues

106
Q

What is the role of ApoB-100 in lipoprotein metabolism

A

ApoB-100 is necessary for the assembly and secretion of VLDL from the liver and is a ligand for the LDL receptor

107
Q

What are the clinical features of familial hypercholesterolemia

A

Features include elevated LDL cholesterol, xanthomas (cholesterol deposits in tendons), and an increased risk of atherosclerosis and coronary artery disease

108
Q

What is the impact of statins on cholesterol metabolism

A

Statins inhibit HMG-CoA reductase, reducing cholesterol synthesis and increasing the clearance of LDL from the bloodstream

109
Q

What are the consequences of a deficiency in carnitine palmitoyltransferase I (CPT I)

A

CPT I deficiency impairs the transport of long-chain fatty acids into the mitochondria for beta-oxidation, leading to hypoglycemia and muscle weakness

110
Q

What is the significance of ApoE in lipid metabolism

A

ApoE is crucial for the clearance of chylomicron remnants and VLDL remnants by the liver

111
Q

What is the role of very low-density lipoprotein (VLDL) in lipid transport

A

VLDL transports triglycerides from the liver to peripheral tissues for energy use or storage

112
Q

What happens to VLDL after triglyceride removal

A

VLDL is converted to intermediate-density lipoprotein (IDL) and eventually to low-density lipoprotein (LDL), which delivers cholesterol to tissues

113
Q

What is the role of high-density lipoprotein (HDL) in cholesterol metabolism

A

HDL is involved in reverse cholesterol transport, carrying cholesterol from peripheral tissues back to the liver for excretion

114
Q

What are the effects of cholesterol ester transfer protein (CETP) on HDL function

A

CETP transfers cholesterol esters from HDL to other lipoproteins, which can influence HDL’s role in reverse cholesterol transport

115
Q

What is the impact of a deficiency in lecithin-cholesterol acyltransferase (LCAT)

A

LCAT deficiency leads to low levels of esterified cholesterol in HDL and can cause corneal opacities, anemia, and kidney dysfunction

116
Q

What is the primary role of chylomicrons in lipid metabolism

A

Chylomicrons transport dietary triglycerides and cholesterol from the intestines to tissues for energy use or storage

117
Q

What is the effect of niacin on lipid profiles

A

Niacin reduces triglycerides and LDL cholesterol while increasing HDL cholesterol

118
Q

What is the role of the liver in lipoprotein metabolism

A

The liver synthesizes VLDL, converts IDL to LDL, and clears chylomicron remnants and HDL cholesterol from the blood

119
Q

What is the function of hormone-sensitive lipase (HSL)

A

HSL hydrolyzes stored triglycerides in adipose tissue into free fatty acids and glycerol, which are released into the bloodstream

120
Q

What triggers the activation of hormone-sensitive lipase (HSL)

A

HSL is activated by epinephrine and glucagon during fasting or stress, leading to the mobilization of stored fats

121
Q

What is the significance of ApoB-48 in lipid transport

A

ApoB-48 is essential for the assembly and secretion of chylomicrons from the intestines

122
Q

What enzyme catalyzes the conversion of cholesterol to pregnenolone

A

Cholesterol side-chain cleavage enzyme (CYP11A1) catalyzes the conversion of cholesterol to pregnenolone, the first step in steroid hormone synthesis

123
Q

What is the role of acetyl-CoA in cholesterol synthesis

A

Acetyl-CoA is the precursor for cholesterol synthesis, which occurs in the cytoplasm and endoplasmic reticulum of liver cells

124
Q

What are the main regulatory steps in cholesterol synthesis

A

The conversion of HMG-CoA to mevalonate by HMG-CoA reductase is the rate-limiting step and key regulatory point in cholesterol synthesis

125
Q

What are the clinical implications of a deficiency in ApoB-100

A

A deficiency in ApoB-100 can lead to familial hypobetalipoproteinemia, characterized by low levels of LDL cholesterol and fat malabsorption

126
Q

What is the function of bile acids in lipid digestion

A

Bile acids emulsify dietary fats in the intestines, aiding in the digestion and absorption of lipids

127
Q

What happens to bile acids after they aid in digestion

A

Bile acids are reabsorbed in the ileum and recycled back to the liver through enterohepatic circulation

128
Q

What is the role of lipoprotein(a) in cardiovascular disease

A

Lipoprotein(a) is a variant of LDL associated with an increased risk of atherosclerosis and cardiovascular disease

129
Q

What are the effects of omega-3 fatty acids on lipid metabolism

A

Omega-3 fatty acids reduce triglyceride levels, have anti-inflammatory effects, and may reduce the risk of cardiovascular disease

130
Q

What is the function of peroxisome proliferator-activated receptors (PPARs) in lipid metabolism

A

PPARs regulate the expression of genes involved in fatty acid oxidation, lipid storage, and insulin sensitivity

131
Q

What are the clinical features of metabolic syndrome

A

Metabolic syndrome is characterized by abdominal obesity, insulin resistance, dyslipidemia, hypertension, and an increased risk of cardiovascular disease

132
Q

What is the impact of insulin resistance on lipid metabolism

A

Insulin resistance leads to increased lipolysis, elevated free fatty acids, and dyslipidemia, contributing to cardiovascular risk

133
Q

What is the role of leptin in energy homeostasis

A

Leptin regulates appetite and energy expenditure by signaling the status of energy stores to the hypothalamus

134
Q

What are the effects of leptin deficiency

A

Leptin deficiency leads to uncontrolled appetite, obesity, and insulin resistance

135
Q

What is the significance of adiponectin in metabolism

A

Adiponectin enhances insulin sensitivity, promotes fatty acid oxidation, and has anti-inflammatory effects

136
Q

What are the consequences of low adiponectin levels

A

Low adiponectin levels are associated with insulin resistance, type 2 diabetes, and increased cardiovascular risk

137
Q

What is the role of AMP-activated protein kinase (AMPK) in metabolism

A

AMPK promotes energy-producing pathways like glucose uptake and fatty acid oxidation, while inhibiting energy-consuming processes like lipogenesis

138
Q

What triggers the activation of AMPK

A

AMPK is activated by an increase in the AMP/ATP ratio, indicating low energy status in the cell

139
Q

What is the role of SREBP in cholesterol and fatty acid synthesis

A

Sterol regulatory element-binding proteins (SREBPs) enhance the transcription of genes involved in cholesterol and fatty acid synthesis

140
Q

What is the function of choline in lipid metabolism

A

Choline is required for the synthesis of phosphatidylcholine, a major component of cell membranes and lipoproteins

141
Q

What are the consequences of choline deficiency

A

Choline deficiency can lead to liver damage, muscle dysfunction, and non-alcoholic fatty liver disease (NAFLD)

142
Q

What enzyme deficiency causes Niemann-Pick disease

A

Niemann-Pick disease is caused by a deficiency in sphingomyelinase, leading to the accumulation of sphingomyelin in cells

143
Q

What are the key features of Gaucher disease

A

Gaucher disease is characterized by hepatosplenomegaly, bone pain, anemia, and the accumulation of glucocerebrosides in macrophages

144
Q

What is the treatment approach for Gaucher disease

A

Treatment includes enzyme replacement therapy with recombinant glucocerebrosidase and, in some cases, substrate reduction therapy

145
Q

What enzyme deficiency leads to Tay-Sachs disease

A

Tay-Sachs disease is caused by a deficiency in hexosaminidase A, leading to the accumulation of GM2 gangliosides in neurons

146
Q

What are the clinical manifestations of Tay-Sachs disease

A

Symptoms include progressive neurodegeneration, cherry-red spots on the macula, and loss of motor skills

147
Q

What is the role of ceramide in sphingolipid metabolism

A

Ceramide is a central molecule in sphingolipid metabolism, serving as a precursor for sphingomyelin and glycosphingolipids

148
Q

What are the consequences of a deficiency in arylsulfatase A

A

A deficiency in arylsulfatase A leads to metachromatic leukodystrophy, characterized by the accumulation of sulfatides and progressive demyelination

149
Q

What is the function of lysosomal acid lipase

A

Lysosomal acid lipase hydrolyzes cholesteryl esters and triglycerides within lysosomes, playing a crucial role in cholesterol metabolism

150
Q

What enzyme deficiency causes Krabbe disease

A

Krabbe disease is caused by a deficiency in galactocerebrosidase, leading to the accumulation of galactocerebrosides and psychosine in the nervous system

151
Q

What are the key features of Krabbe disease

A

Symptoms include developmental delay, optic atrophy, peripheral neuropathy, and early death

152
Q

What is the impact of a deficiency in alpha-galactosidase A

A

A deficiency in alpha-galactosidase A causes Fabry disease, characterized by angiokeratomas, kidney failure, and neuropathic pain

153
Q

What is the role of glucocerebrosidase in lipid metabolism

A

Glucocerebrosidase breaks down glucocerebrosides into glucose and ceramide, preventing their accumulation in cells

154
Q

What is the clinical significance of lysosomal storage diseases

A

Lysosomal storage diseases result from deficiencies in enzymes required for the degradation of specific biomolecules, leading to their accumulation and causing cellular dysfunction and disease

Noorda FOM (18 decks)

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