Biochemistry Diseases Flashcards
Kwashiorkor
diet adequate in calories but LOW in PROTEINS
- low serum albumin levels
- malabsorption
- hepatomegaly and distended abdomen
- bloating
marasmus
diet low in BOTH protein and calories
starvation –> death
cystic fibrosis
defect in CFTR channel
can’t reabsorb excess Cl- anions
causes diarrhea
cholera
opens CFTR channel (via cAMP)
efflux of Cl- and water into intestines
maple syrup urine disease
defect in ketoacid transamidase (catabolism in branched chain aas)
Val, Leu, and Ile increased in urine
PKU
(-) phenylalanine hydroxylase
or
(-) BH4 synthesis (cofactor)
can’t degrade Phe –> Tyrosine
- mental retardation since Tyrosine is needed to make catecholamines
Tx = Kuvan
cystinuria
defect in Cys reabsorption in kidneys and small intestines
calcali in urine, kidneys, and bladder
Kuru
prion disease due to new guinea cannibalism
sickle cell anemia
mutation in beta chain in Hgb
glutamate –> valine (negative –> hydrophobic)
RBCs have sickle cell shape (hemolysis and anemia)
carbon monoxide poisoning
tight binding of CO to iron in heme
230X grater than O2 affinity for heme
Ehlers-Danlos Syndrome
mutation in synthesis and processing of collagen
abnormalities of skin, ligaments, and organs
skin = fragile and stretches easily
osteogenesis imperfecta
type I collagen genes
bones fragile, easily fracture
scurvy
vitamin C deficiency –> hydroxylation of proline residues is decreased and unstable form of collagen made
bones, teeth, BVs develope abnormally
bleeding gums and poor wound healing
marfans
fibrillin
tall stature with arachnodactyly
mitral valve prolapse
lens dislocation
alport syndrome
type IV collagen
meshlike collagen network in kidney…cells cannot form and filter waste from blood
leads to kidney failure
hereditary spherocytosis
mutations in RBC membrane proteins (spectrin and ankyrin)
hemolytic anemia
splenomegaly
familial hypertrophic cardiomyopathy
mutation in beta-myosin heavy chain of sacromere proteins
thickening of heart muscle
sudden death under exercising conditions
emphysea and liver damage
A1-antitrypsin (inhibits elastase action in lungs)
elastase can destroy lungs
accumulation of defective A1-AT damages liver tissue
UV light
makes pyrimidine dimers in DNA
very pronounced in xeroderma pigmentosum (XP) because their DNA repair system does not work (defect in NER)
Hereditary nonpolyposis colorectal cancer (HNPCC) or Lynch syndrome
autosomal dominant
mutation in MLH1 and MLH2 (mismatch excision repair)
risk for cancer goes way up
Bloom-Torre-Machacek syndrome
mutation in helicase
short stature, and risk for cancer and DNA instability
autosomal recessive
Cockayne syndrome
mutation in transcription-couple DNA repair
premature aging
Chronic myeloid leukemia (CML)
due to philadelphia chromosome (translocation between 9 and 22) –> bcr-abl
bcr-abl kinase = oncoprotein kinase
Treatment = imantinib = inhibits this enzyme
alpha-amanitin
death cap mushroom
inhibits eukaryotic RNAp (especially RNA Poly III)
- binds to backside and inhibits synthesis
causes GI problems
then death
Hemoglobin C
poitin mutation in beat-globin chain in Hgb
mild anemia
no sickling
beta-thalassemia
excess in alpha subunits in heme
decrease in Hgb A
increase in Hbg A2
anemia and cells appear hypochromic
Beta+ mutation = reduced expression of beta-globin
Cooleys anemia
absence of beta globin
alpha thalassemia
excess in beta subunits in heme
Ricin (castor beans)
inhibits protein synthesis by acting like N-glucosidase
depurinates adenine bases in 28rRNA –> which then degrades
inhibition of translation
symptoms:
abdominal pain and vomiting
bloody stool
Rett syndrome
mutation in MECP2 (codes for methylated DNA binding protein in brain which recruits HDACs)
loss of communication and use of hands
muscular dystrophy
lots of different types due to mutations on dystrophin locus (Iongest gene)
Duchenne = lack of dystrophin; survival rare past 30
Becker = low expression
Burkitt Lymphoma
non-Hodgkin’s
translocation of protooncogene = Myc
usually chromosome 8 or 14
Myc inappropriately expressed in cell cycle –> inappropriate cell growth
- one form linked to Epstein-Barr Virus
Wilm’s Tumor
loss of function of WT1
mutated zinc-finger transcription factor
solid abdominal tumor in children (90% of kidney cancer)
Myotonic dystrophy
DMPK gene
repeated CTG repeats (more = more severe)
continuous firing of musclees
cardiac problems
insulin resistance
myotonia
leukoencephalopathy with CNS hypomyelination and Vanishing white matter
missense mutation in eIF2
seizures and degeneration of white matter
recall eIF2 mediates formation of preinitiation complex
also plays role in cell stress response
glial cell death, loss of myelin sheath, neurological deterioration
Alzheimers
due to PSEN1 or PSEN2 mutation
beta amyloid plaques and intracellular neurofibrillary tangles
huntington’s disease
CAG repeats in ORF (>40)
= HTT misfolds –> mHTT
interfere with NT release –> neuronal cell death
parkinson’s
aggregates of misfolded alpha-synuclein –> aggregates
= Lewy bodies
death of dopaminergic neurons
ALS (lou gehrigs)
superoxide dismutase protein (SOD1)
misfolds and aggregates
spinal cerebellar ataxia
ataxin with CAG repeats
mucopolysaccharidoses (MPS)
deficiency of enzymes that catabolize GAGs
accumulate GAGs in various tissues
Icell disease
problem targeting lysosomal proteins to organelles
missing mannose-6-phosphate signal (M6P)
Spingolipidoses (GSL storage disease)
excessive accumulation og GSL in lysosomes
caused by impaired lysosomal degradation of specifc GSL
Fabry disease
mutation in alpha-galactosidase A
Gb3 increases
Gaucher’s disease
(-) glucocerebrosidase A
GlcCer increases
treatment = Cerezyme
Krabbe disease = globoid cell leukodystrophy
(-) galactocerebrosidase (GALC)
***no rise in GalCer …. but rise in psychosine
severe demyelination of CNS and PNS
Tay Sachs
(-) hexoaminidase
GalNAc accumulates
Niemann Pick diseaes
sphingomyelinase
MERRF
mitochondria epilepsy with ragged red fibers
ragged red fibers…
Zellweger Syndrome
peroxisomes not produced properly
VLCFA aummulate
- bile acid and plasmalogen synthesis affected –> large liver
myelin structure altered due to accumulation of FAs (especially Phytanic acid)
androgen insensitivity
mutated androgen receptor
can’t respond to androgens
ambiguous genitalia
myasthenia gravis (autoimmune)
antibodies against ACh receptor
muscle fatigue
Severe combined immunodeficiency, SCID
Adenosine deaminase (ADA) deficiency
–> high levels of dATP –> no DNA synthesis
affects T and B cells
whooping cough (bordatella pertussis)
toxin ADP-ribosylates a G-alpha-i subunit (inhibitory)
continually active signal in lung cells
increased PKA –> activates CFTR –> fluid loss as mucus into lungs
breast cancer
mutation in BRCA1 or BRCA2
treatment = tamoxifen
or Herceptin for HER2 cancers
- vitamin A
night blindness
xerophthalmia
- vitamin D
inadequate bone mineralization
rickets
osteomalcia
- vitamin E
reproductive failure
muscular dystrophy
neuro
- vitamin K
defective blood clotting
- thiamine
beriberi
wernicke-korsakoff
- riboflavin
oral-buccal cavity lesions
- niacin
pellagra
- B6 (PLP)
convulsions
dermiatitis
anemia
- folate
megaloblastic anemia
- B12
pernicious anemia
neuro
- biotin
scaly dermitis
anorexia
- panthothenic acid
listlessness
fatigue
burning feet syndrome
arsenic poisoning
inhibits enzymes/cofcators with free sulfhydryl groups
like….
lipod acid (PPP) pyruvate DH (PDH) alpha-KG DH (CAC)
cyanide poisoning
cyanide binding to Fe3+ in cytochrome aa3
O2 can’t receive e-respiration inhibited energy production stops
death
Leigh’s disease
subacute necrotizing encephalopathy
mutations in PDH complex - usually E1
hunter syndrome
mucopolysaccharidose
- iduronate sulfatase
buildup of DS and HS in lysosome
hurler syndrome
mucopolysaccharidose
- alpha-L-iduronsidase
buildup in DS and HS in lysosome
sanfillippo syndrome
mucopolysaccharidose
HS buildup
hemolytic anemia
- in PK or G6PDH (no NADPH)
usually benign unless have a hemolytic crisis
(need to convert more 1,3 BPG –> 2,3 BPG)
fructosuria
fructokinase
benign
fructosemia (fructose intolerance)
fructose-1-P aldolase (aldolase B)
severe hypoglycemia
galactosemia
galactokinase
cataracts
classic galactosemia
galactose-1P uridyly transferase
liver damage - hypoglycemia
tangier disease
ABC1 protein
HDL particles are choletserol poor –> reduced level of HDL in circulation
leads to premature CHD
familial hypercholesterolemia
LDL receptors
xanthomas, CAD
hypertriglyceridemia
(-) LDL or ApoC (Activates lipoprotein lipase)
high TG due to decreased degradation of VLDL and chylomicrons
seen in diabetes
carnitine deficiency (primary)
CAT1 or CAT2
can’t transport carnitine into cells that need it
reduced FA oxidation
can cause hypoketotic hypoglycemia
- low ketone bodies; low gluconeogenesis so low BG
carnitine deficiency (secondary)
liver disease, malnutrition, vegan
accumulation of acylcarnitine derivatives = toxic
cardiac arrest
MCADD (medium chain acyl-CoA DH deficiency)
prevents use of FAs as fuels
hypoglycemia
Hartnup disease
transport of neutral AAs defective
deficiency of essential aa
leads to a niacin deficiency (made from tryptophan)
homocystinuria
cystathionine synthase (so HC + serine –> cystein doesn’t work)
treatment with increased vitamin B6 (PLP) = cofactor
associated with CAD
alcaptonuria
homogenistate oxidase
degenerative arthritis
tyrosinemia type I
fumaryl=acetoacetate hydrolase
accumulation of gumarylacetoacetate –> liver and kidney failure
cabbage urine odor
tyrosinemia type II
tyrosine aminotransferase
eyes, skin, mental development
albinism
tyrosinase - so tyrosine cannot be converted to melanin
Lesch-Nyhan syndrome
hypoxanthine guanine phosphoribosyltransferase (HGPRT)
purine bases can’t be salvaged - converted to uric acid instead –> gout
self-mutiliation!!!!
gout
underexcretion (primary cause) or overproduction of uric acid
orotic acidemia
UMP synthetase
orotate phosphoribosyl transferase
oridine phosphate decarboxylase
pyrimidines cannot be made
growth retardation
treat with uridine
lead poisoning
inhibits step 2 and last step of heme production
heme production decreased– > anemia
porphyria
deficiency in enzyme of heme production
neuropsychiatric symptoms due to accumulation of intermediates
photosensitivity due to accumulation of porphyrinogens which react with light to produce ROS
congenital adrenal hyperplasia
- 21alpha-hydroxylase (most common)
- excess androgens - 11beta
- androgens in excess (low renin-HTN) - 17alph
- MRs in excess
Von Gierkes
glycogen storage disease
glucose 6 phosphatase
enlarged liver
hypoglycemia
Hers disease
glycogen storage disease
liver phosphorylase
can’t convery glycogen –> BG
pompe disease
glycogen storage disease
lysosomal glucosidase
glycogen accumulates in liver
McArdle disease
glycogen storage disease
muscle phosphorylase
virgorous exercise –> fatigue