BCHM Facts-PreMid

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BCHM Facts-PreMid
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Random BCHM Facts
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  1. Arsenic poisoning
    • Arsenite- most toxic form
    • Acts on enzymes containinglipoic acid (ex: PDH, glyceraldehyde 3 phophate dehydrogenase) Reoxidizes the reduceddisulfide bond --> increases its stability so pyruvate and lactatebuilds upCauses a decrease in E.production ---> acidosis Treatment: 2,3 mercappropanol(competes w lipoic acid)
  2. Thiamine Deficiency
    • Deficiency in thiamine
    • (vitamin B1) results in PDH complex E1 not being able to decarboxylate
    • pyruvate because the enzyme will present as an apoenzyme with no thiamine
    • pyrophosphate cofactor bound to it
  3. Mild deficiency: GI
    • complaints, "pins and needles"/burning feet
    • Severe deficiency: Beri-Beri
    • or Wernicke-korsakoff Syndrome
  4. Beri Beri
    • Asia- eating polished rice with husk removed (source of thyiamine)
    • Wet and dry type- depending
    • if edema is present or not
    • Nueromuscular cardiovascular
    • disorders, delirium, memory loss, muscle weakining, increased venous
    • return to heart, peripheral vasodilation, opthalomogplegia
    • Death by high output cardiac
    • failure
  5. Wernicke-Korsakoff Syndrome
    • Chronic Alcohol abuse and poor nutrition
    • Wernicke's encephalopathy(acute phase): delerium, mental derangement, ataxia, opthalmoplegia
    • Korsakoff psychosis (chronicphase)- anterograde amnesia, distinct pattern of brain damage (focaladhesions) …IRREVERSIBLE
    • Diagnosis- urinary thiamineexcretion, transketolase activity in RBC, lactate/pyruvate levelspost-oral glucose pill
    • Treatment- thiamineinjections intramuscularly (before chronic phase)
  6. Leber
    Hereditary Optic Neuropathy

    (LHON)
    • affects complex I
    • Optical nerve damage - lossof bilateral vision
    • passed onto all offspring
  7. Myoclonic Epilepsy and Ragged Red Fiber Disease
    (MERRF)
    • Mutation in tRNA for lysine (encoded by mt)
    • Late childhood -->
    • adulthood
    • Myoclonus- uncontrollable
    • muscle jerking
    • Seizures, lactic acidosis,
    • dementia, cardiac problems
    • Ragged red fibers = clumbs of
    • enlarged mito
  8. Mitochondrial
    Encephalomyopathy, Lactic Acidosis, & Stroke Like episodes (MELAS)
    "lactic leucy"

    • Mutation in tRNA leucine
    • 5-15 yo age onset
    • Stroke
    • Lactic acid - vomiting,
    • tiredness, muscle weakness
  9. Aminoglycoside
    Induced Deafness
    "12 GENTlemen with STREPthroat"

    • Mutation in 12s rRNA
    • Streptomycin and gentamysin
    • binds to 12s rRNA
    • No translation of ATP
    • synthase
  10. Inhibotors of ATP/ADP
    plant toxins- deplete ADP, shuts down ETC, but reactivated w uncouplers

    Atracyloside (mold toxin)-acts on cytosolic side

    Bongkrekic acid- acts onmatrix side
  11. Plant toxins- deplete ADP ,
  12. 2,4 Dinitrophenol
    • -chemical uncoupler
    • Benzene ring w 2 nitro groups
    • and a dissociable H+
    • High [H+] in intermembrane
    • can add to deprotonated 2,4 DNP
    • Protonated (uncharged) form can pass through membrane into
    • matrix
    • H+ is released into matrix
  13. Valinomycin
    chem uncoupler

    • Antibiotic that makes inner
    • membrane permeable to K+
    • No proton motive force, but
    • proton gradient remains (?)
  14. Gramicidin A
    • chem uncoupler
    • orms non-specific
    • channel that allows H+ to pass through
  15. Retenone (natural insecticide piercidin
    A)
    Amytal (barbituate)
    • prevents donation of
    • e- from Fe-S to CoQ
  16. Antimycin A (antibiotics)
    • prevents e- donation
    • from complex III to cyt c
  17. Cyanide, azide
    Hydrogen sulfide (binds to
    Fe3+)
    Carbon monoxide (binds to
    Fe2+)
    • Build up of reduced
    • compondents of all complexes
  18. What are the irreversible steps of glycolysis?
    PEP --> pyruvate [bypassed with pyruvate carboxylase]

    F6P --> F16BP [bypassed with F16BPase]

    Glucose --> G6P [bypassed with g6pase]

    Remeber- the 1st, exact middle, and last steps of glycolysis are irreversible. Must be bypassed in gluconeogenesis to go from pyruvate --> glucose
  19. Von Gierke
    • Type I liver glycogenosis
    • G6Pase enzyme defect

    • Affects liver, intestinal
    • mucosa, kidneys
    • Failure to dephos. =
    • hypoclycemia & hepatomegaly
    • Most common glycogen storage disease
    • Lactic
    • acidaemia-
    • glucagon enhances lactate production
    • Hyperlipidaemia

    • Type 1B- deficient in G6P
    • transporter (same results)


    • Avoid fasting
    • Uncooked
    • cornstarch
    • Nasogastric
    • tube- to infuse
    • CHO when sleeping
  20. Coris Disease
    • Type III liver gluconeogenesis
    • amylo-1,5-glucosidace debranching enzyme


    • Affects liver, myocardium,
    • skeletal muscle
    • VERY MILD
    • Glycogen molecule has
    • abnormal structure w short outer branches
    • Unable to metabolize beyond
    • branch points
    • Hepatomegaly, myopathy,
    • asymptomatic hypertrophic cardiomyopathy in elderly
  21. Anders Disease
    • Type 4 liver glucogenosis
    • -branching enzyme defect

    • -severe and fatal
    • -liver cirrhosis
    • -glycogen has long unbranched chains so not soluble
    • -very rare
    • -autoimmune attack on tissues
    • -treatment: liver transplant
  22. Her's Disease
    Type 6 Liver glycogenosis

    • - defect in liver phosphorylase
    • -hepatomegaly and hypoglycemia
  23. O Glycogenosis Disease
    defect in hepatic glycogen synthase

    • -unable to synthesize glycogen at all
    • -fluctuates b/w hypo and hyperglycemia
  24. Popmpe's Disease
    -lysosomal alpha 1-4 enzyme defect

    • -generalized glycogenosis (liver, heart, muscle)
    • -lysosome overstuffed with glycogen
    • -affects brainstem and spinal cord
    • -infants- severe- die in less than a year
    • -juvinille and adults- moderate
  25. McArdle's Disease
    • Enzyme deficiency is muscul phosphorylase
    • -elevated CKMM levels- caused by muscle dystrophy and proteolysis
    • -myoglobinuria- brow/red urine
    • -myocytes become damaged due to glycogen buildup
    • -cramps upon exercising

    • treatment: High protein diet,
    • creatine supplements
  26. Tauri's Disease
    Defect in PFK1 enzyme

    • -
    • Muscle weakness and cramping
    • Hemolysis can occur due to low PFK
    • acvitivty in RBCs
  27. Chronic Granulomatous Disease
    • (CGD)- Phagocytes have a defective NADH oxidase so they cannot produce
    • superoxide anions to combat infection (usually caused by beta subunit)
  28. Causes recurrent life
    • threatening bacterial and fungal infections
    • Granulomas often found in
    • skin, GI tract, urinary tract
  29. Granuloma- collection of
    • macrophages (often presents as
    • trouble breathing)
  30. Superoxidedismutase (SOD)
    - reverses (dismutases) of superoxide back to O2
  31. O2- --> H202 (not toxic
    unless converted to a toxic species)
  32. Releases oxygen for the
    conversion
  33. Cytosolic isoform- requires
    • Cu+ or Zn+
    • Extracellular- requires Cu+
    • or Zn+
    • Mitochondrial- requires Mn+
  34. Since these are all +
    charged, O2 immediately binds to it
  35. Glutothione
    in cytosol and mitochondria
  36. Reduces peroxide to water
    • Reduces lipid peroxides to
    • alcohol
  37. Catalase
    H202 --> 2H20 + O2

    • Mostly found in liver and
    • kidney (b/c that’s where most
    • peroxisomes are)
  38. Dietary Antioxidants
    Vitamin E

    • Contains tocopherols (AOX) -
    • terminates free radical chain reactions of lipid peroxidation
    • Alpha isomer- against ROS
    • Gama isomer- against RNOS
    • (Think Taco = fat = use vitamin E)



    Vitamin C- regenerates the reduced form of Vitamin E

    • Caretenoids-
    • can get rid of oxygen radicals with its long conjugated double bonds
  39. Uric Acid (Endogenous Scavenger)
    • Scavenges OH radicals,
    • peroxyradicals, and oxyheme radicals
    • Uric acid is water soluble so
    • it can enter the plasma, saliva, and lung lining fluid along with protein
    • thiols to scavenge free radicals
  40. Vmax
    occurs when enzyme is fully saturated with substrate, and therefore indicates strength of an enzyme
  41. Km
    [substrate] needed to reach half of Vmax

    note: small km = HIGH substrate affinity for the enzyme
  42. Competitive vs Noncompetitive Inhibitor
    • Competitive- chemical analogue of the natural enzyme so they compete for the same active site since they will both fit
    • same v max, km increases
    • easily overcome by increasing [substrate] to have more of it than the inhibitor

    • Noncompetitive- works at a different active site
    • same kM
    • lower Vmax
  43. Alkaline Phosphate (ALP)
    • pathological: biomarker for bone or liver disease
    • physiological: increased during pregnancy and childhood growth

    "The people in the ALPs have Paget's Disease"
  44. Creatine Kinase Isoforms (1,2,3)
    • CK1- BB- brain, lungs
    • CK2- MB - myocardium * (used for heart attack biomarker)
    • CK3- MM - myocardium and muscle
  45. Liver Biomarkers
    • Alanine AminoTransferase (ALT)- liver only
    • Aspartate Aminotransferase (AST)- heart,muscles, liver
    • Alkaline phosphate (ALP)- bone and liver

    *there are others (unimportant)
  46. Which MI biomarker is most sensitive, most specific, gives longest diagnostic window, and servesto confirm diagnosis?
    • CKMB2- most specific
    • Myoglobin- most sensitive (fastest)
    • Troponin- longest window (3-12 hrs)
    • LDH- confirms with 1,2 flip
  47. Coupling in Series vs Parallel
    • Series: product of 1st rxn becomes substrate of the 2nd rxn
    • Parallel: energy to drive a specific rxn forward comes from energy released by a side (parallel) rxn
  48. Triphosphate Nucleotides
    • Uracil Triphosphate (UTP)- carbohydrate synthesis
    • Cytidine Triphosphate (CTP) - lipid synthesis
    • Guanosine Triphosphate (GTP)- protein synthesis
  49. Adenylate Kinase
    ATP + AMP --> [AK] --> ADP
  50. 1,3 biphosphoglycerate
    • high energy compound in the glycolytic cycle
    • normally converts to 3 phosphoglycerate but in RBC it is shunted away to form 2,3 BPG [via 3BPG mutase]
    • holds hemoglobin in the T state
  51. Nucleotide Structure
    DNA vs RNA structure
    • N base @ C1
    • Pi group @ C5
    • DNA= OH at C2
    • RNA= OH at C2 and C3
  52. snRNA, miRNA
    • small nuclear RNA- used for intron splicing
    • micro RNA- regulates genome expresssion through cleavage
  53. Negative vs Positive Supercoiling
    • Negative- underwound, left handed direction
    • Positive- overwound, right handed direction
  54. Topioisomeriase (I & II)
    Topiosiomerase- cut DNA strands and then reseals them to form supercoils

    I- cuts one strand, passes the other through the gate, and then rejoins them. Removes one twist @ a time

    II- (Gyrase)- cuts both strands to remove 2 twists at a time
  55. Levels of Histone Packaging1
    1. nucleosome (8 histones + linker DNA) forming "beads on a string"

    2. solenoid- 30 nm fibers formed by many packed nucleosomes arranged on a scaffold/matrix
  56. Acetylation & Methylation of Histones
    Acetylation: removes the histones + charge, reducing the affinity b/w histones and its wrapped DNA, allowing the DNA to be free for transcription

    Methylation: tightens DNA around histones forming heterochromatin (transcriptional silencing)
  57. Which direction is DNA read?
    5' --> 3'
  58. Types of Prokaryotic DNA polymerase
    • Pol I - excises RNA primer
    • Pol II - repair damage
    • Pol III- elongates primer
  59. Difference b/w Top I in prok and euks
    • prok- only relieves - supercoils
    • euk- relieves + and - supercoils
  60. Overview of Top differences b/w Prok I and II
    • Topoisomerase I - can only relax coils
    • ----prok- relaxes (-) coils
    • ----euk- relaxes (-/+) coils

    • Top II (pro)- does everything (intro +/-, relaxes +/-)
    • Top II (euk)- does everything EXCEPT intro (-)
  61. Types of Euk/Prok RNA Polymerase
    Prok: RNA Pol I - binds to sigma factor to make holoenzyme to begin transcription (terminated via rho factor)

    • Euk:
    • Poly I - rRNA
    • Poly II- mRNA
    • Poly III - tRNA
  62. Splice Junction
    • 5' GU donor site (U1)
    • 3' AG acceptor site
    • middle = A = branch site

    U2- forms the lariant structure that is eventually cleaved
  63. A to I RNA Editing
    • occurs due to adenosine deaminase-- the intron and exon are complimentary to each other so they form a double stranded RNA structure that attracts an ADAR enzyme to it that causes the editing
    • without editing the gene woudl conduct Na+ and Ca2+
    • with the editing the gene conducts only Na+
    • important for memory and learning
  64. Stop Codons. Start codon
    • UAA
    • UAG
    • UGA

    [all start w uracil]

    start = AUG (Met)
  65. Insulin Cleavage
    • Preproinsulin- contains a signal sequence that brings it to the ER
    • Proinsulin- forms inside the ER when the signal sequence is cleaved
    • Insulin- removal of big internal C-peptide, leaving behind the disulfide bonded insulin (the C peptide has the info on how to fold, but once folded is not needed)
  66. Farnesyl & geranylgeranyl
    anchors lipids to the plasma membrane
  67. O glycosylation vs N glycosylation
    • O: occurs in gOlgi .... carb attaches to OH gp (of Ser or Thr)
    • N: occurs in RER ...carb attaches to amide N (of Asp)....more common glycosylation, assists in protein folding
  68. Important long chain FA (note essentials)
    P-SOLaA

    • Palmitic: 16-0
    • Steric: 18-0
    • Oleic: 18-1
    • Linoleic: 18-2 * w6
    • alpha Linoleic: 18-3 * w3
    • Arachadonic: 20-4 *w6

    essential FA* = anything the body cant produce and is part of the w3 or w6 family (....LaA)
  69. Diphosphatidylglycerol
    • aka cardiolipin- holds the ETC together
    • Barth syndrome- acyl transferase inhibited from converting lysosomal CL to regular CL so lysosomal CL builds up causing cardiohypertrophy
  70. Plasmalogen
    phospholipid where the HC chain is attached to the C1 OH of glycerol (??)
  71. Polyisoprenoid
    group of lipids that share an initial common pathway and result in 5C isoprene units
  72. Sterol/Steryl Esters
    • synthesized from 5C isoprene units (that come from polyisoprenoids)
    • form sterioids (ex: cholesterol)
  73. Sphigomyelin (location, head gp)
    • [e sphingolipid]
    • location: myelin sheath
    • head group: phosphocoline, phosphethanolamine
  74. Galactoerabroside (location, head gp)
    • [e sphingolipid]
    • location: neuronal cell membranes
    • head group: galactose
  75. Ganglioside (location, head gp)
    • [e sphingolipid]
    • location: gray matter of CNS
    • head group: 3+ sugar gp + sialic acid residue

    -multiple sclerosis, niemann pick disease
  76. What is the lipid in Lung Surfactant?
    dipalmitoylphosphatidylcholine

    • di- dead baby
    • palm/toyl - baby w toy in his palm
  77. Unsaturated vs Saturated bond
    • Unsaturated: loosely packed due to double bonds, therefore increases fluidity
    • Saturated: tightly packed together due to single bonds, and therfore increases rigidity
  78. Passive transport
    • H --> L
    • simple diffusion
    • facilitated diffusion
    • protein transport carriers -uni/symp/antiport
  79. Primary vs Secondary Active Transport
    • primary: gains energy for L--> H transport via ATP
    • secondary: gains energy for L--> H transport via Na+/H+ concentration gradient
  80. GLUT transporters
    • Glut 1 + 3 = brain (low km)
    • Glut 2= liver (high km)
    • Glut 4 = muscle, adipose (low km, insulin dependent)
    • Glut 5= small intestine (fructose transporter)
  81. Peptide vs Secondary Hormones
    • Peptide: acts on a receptor outside the membrane
    • Secondart: lipid soluble, so enters cytoplasm or nucleus and therefore can affect gene transcription
  82. Tyrosine is precursor for...?
    epinephrine/norepinephrine, dopamine (Parkinsons)
  83. Tryptophan is precursor for...?
    seretonin (sleep cycle/depression/gut fnx)
  84. Low Mr Signaling Receptors
    Nitric Oxide ---> stimulates guanylate cyclase --> generates cGMP (second messenger)-vasodilator
  85. Enzyme Linked receptors
    insulin + tyrosine receptor --> phosphorylates insulin receptor subunits (IRS) --> various biological pathways
  86. Lipid soluble receptors
    • steroids/cholesterol: androgens, mineralcorticoids, glucocorticoids
    • intracellular regulation
  87. G Protein Linked Receptors
    • 1- signal binds to receptor
    • 2- receptor changes confirmation
    • 3- change activates G protein and its supbunits to bind GTP (active)
    • 4- alpha subunit dissociates to activate a target enzyme:
    • ----adenylate cyclase: Atp --> cAMP (2nd mess)
    • ----phospholipase C: PIP2 --> IP3 + DAG + Ca2+
    • 5- alpha subunit binds back to GTP to make it GDP (inactive)
  88. Ion Gated Receptor
    ex: nicotonic choilinergic neuroreceptors (Na+/K+ influx @ neuromuscular Jnx)
  89. D configuration
    alpha anomer
    beta anomer
    • D configuration- OH on Right of highest # C in Fisher
    • Alpha- OH points down
    • Beta- OH points up
  90. Reducing Sugar
    • if the anomeric OH of a ring is not involved in a reaction, it can act as a reducing sugar
    • -all monosacharrides
    • -all disaccharides (except sucrose!)
    • -all polysachharides (but only weakly reducing)
  91. Sucrose breakdown
    Associated Diseases
    Sucrose --> Glucose + fructose

    • -fructose malabsorption --> IBS
    • -hereditary fructose intolerance (aldolase B deficiency)
  92. Lactose Breakdown
    Associated diseases
    • Lactose --> glucose + galactose
    • Lactose intollerance- missing lactase enzyme
  93. Storage Polysaccharides
    • Plants use starch
    • --amylopectin (70%)- branched alpha 1,4 and alpha 1,6
    • --amylose (30%)- unbranched alpha 1,4

    • Animals use glycogen (muscles & liver)
    • ---many branches, alpha 1,6
  94. Glycosaminoglycan (GAG)
    • long chain branched heteropolysaccharide
    • highly negative and slippery (shock absorber, synovial fluid, vitreuous humor, umbilical cord)
    • -made up of repeated disacharide units
  95. PDH Complex Enzymes and Coeznyme
    • E1- PDH (thyamine pyrophosphate TPP)
    • E2- Dihydrolipoyl Transacytlase (lipoic acid & co-A)
    • E3- Dihydrolipoyl Dehydrogenase (FAD & NAD+)
  96. Regulation of PDH complex
    • Pyruvate Dehydrogenase Kinase: adds Pi to E1, deactivatin it
    • ---regulatory molecules to turn PDH off: NADH, ATP, acetyl co A

    • Pyruvate Dehydrogenase Phosphotase: removes Pi, activating E1
    • ---regulatory molecules to turn on PDH: NAD+, ADP, coA, pyruvate, Ca2+
  97. Anabolic biosynthetic intermediates of TCA
    • citrate -- FA synth
    • alpha keto glutarate --- glutamine + NT (GABA)
    • succinyl co A --- heme synthesis
    • malate -- gluconeogenesis
    • OAA -- AA synthesis
  98. What is the purpose of mitochondrial shuttles?
    to convert cytosolic NADH back to NAD+
  99. What is oxidative phosphorylation?
    coupling ETC to ATP synthase
  100. Oligomycin
    binds to Fo pore portion of ATP synthase , inhibitng ATP synthesis by inhibiting H+ ions to enter the channel
  101. What do uncouplers do?
    uncouple oxidative phosphorylation (H+ enters matrix without Fo channel of ATP synthase and doesnt produce ATP but rather uses the Energy as Heat)
  102. 2,4 Dinitrophenol
    • chemical uncoupler
    • benzene ring 2 2 nitro groups and a dissociable H+
    • high [H]+ in intermembrane can add to deprotonated 2,4 DNP
    • protonated (uncharrged) form cann mass through membrane into matrix
    • H+ released into matrix
  103. Valinomycin
    • Chemical Uncoupler
    • antibiotic that makes the inner membrane permeable to K+
    • no proton motive force, but gradient remains
  104. Gramicidin A
    forms a non-specific channel that allows H+ to pass through
  105. Physiological uncouplers
    • utilize uncoupling proteins to uncouple ETC from ATP synthase
    • form H+ channels through inner mito membrane to allow H+ flow
    • UCP1= brown adipose (thermogenin)
    • UCP2= most cells
    • UCP3= skeletal muscles
    • UCP4 & 5= brain
  106. Nonshivering Thermogenesis
    TAG > [lipase] > FA + glycerol > [blocks ATP synthase so E cant be produced so instead...] > Heat is produced!
  107. How does ATP/ADP travel through the mitochondrial membranes?
    • Outter membrane: use VDACS- non specific pore
    • Inner membrane: use adenosine nucleotide translocase (ANT) that allows an antiport ATP:ADP 1:1 exchange
  108. Inhibitors of ATP/ADP transport across membranes
    • atractyloside (mold toxin): inhibits transport on the cytosolic side
    • bongkreik acid: inhibits transport on matrix side

    *both act on adenosine nucleotide translocase (ANT)
  109. F26BP
    • -signaling molecule to activate glycolysis
    • -F16BP --> [PFK2] --> F26BP stimulates PFK1 to activate glycolysis
  110. Fed State effect on Liver Glycogen Metabolism
    • increase protein phosphorylase
    • activates glycogen synthase
    • increases glycogen
  111. Fasted State on Liver Glycogen Metabolism
    • Increase protein kinase
    • activates glycogen phosphorylase
    • increases glucose
  112. Types of ROS
    • super oxides (o2-)
    • hydrogen peroxides (h2o2)
    • hydroxyl radical (OH.)
  113. Types of RNOS
    • Nitric Oxide (NO-)
    • peroxynitrite (ONOO-)
  114. Spin forbidden
    • Refers to the fact that Oxygen has 2 unpaired e- in 2 different orbitals
    • therefore, inorder to react, an atom needs to donate 2 PARALLEL pairs of e- (which is not common...)
    • therefore oxygen is known as a "stable" radical
  115. Fenton Reaction
    hydrogen peroxide converting to a hydroxyl radical via Cu or Fe transition metal

    common in crush injuries where lots of Fe are released
  116. Haber Weiss Reaction
    Similar to Fenton Rxn, except requires O2 superoxide to react with H202

    H202 + O2 ---> hydroxyl radical
  117. Most commonly damaged AA due to free radical exposure
    • Cystine
    • Arginine
    • Methionine
    • Proline

    CAMP
  118. Describe Oxidative Lipid Damage
    • due to lipids in the presence of free radicals
    • produces peroxyl lipids (LOO.) and lipid peroxides (H2OL)
    • degrades to malondialdehyde....toxic and dangerous to DNA
  119. Where do ROS come from? Most superoxides?
    • produced deliberately (ex: in inflammation)
    • accidental products of normal reactions
    • exogenous: ionizing radiation, UV, toxic chemicals, drugs
    • most superoxides come from CoQ of the ETC
  120. Mono-oxygenase
    • enzyme that adds one atom of O2 to water and the other into the substarte
    • ex: Cytochrome P450
    • elevated in chronic alcoholics because because ethanol metabolism releases acetyl aldehyde which later releases free radicals
    • liver cirrhosis --> fibrosis
  121. Physiological Fnxs of ROS
    • NO- smooth muscle relaxation, NTs
    • superoxides- blood pressure, signal transduction, controls ventillation
  122. Physiological Fnxs of RNOS (& their regulation)
    • I: neurotransmitters (Ca2+)
    • II: fight infection (inducible, cytokines or bacterial lipolysaccharides)
    • III: vasodilator (ca2+)
  123. Isoform II RNOS
    • main source of RNOS
    • activates NADPH Oxidase Complex
    • Neutrophil > produces NO > activates NADPH oxidase > uses O2 to make superoxides to fight infection
    • (cataylytic beta subunit transfers e- from NADPH to FAD) defective beta subunit usually leads to Chronic Granulomatous Diseas --> cant fight infection
  124. Functions of NADPH
    • synthesis of NT, FA, Steroids, Cholesterol
    • detoxification of ROS via reducing glutathione
    • Generate respiratory bursts- from attacking ROS
    • nitric oxide signaling- vasodilation
  125. PPPs relation to RBCs
    • Most cells can produce NADPH in alternative methods besides PPP by using malate dehydrogenaseRBCs cannot, so relies fully on PPP
    • deficiency of G6P leads to heinz bodies- denatured proteins in RBC that due to lack of NADPH
    • breakdown of RBCs leads to anemia and jaundice
  126. Why are most people with G6PD deficiency resistant to malaria?
    Malarial parasites require reduced glutothione and PPP productss to grow, so without them, they die
  127. Preciptitating Factors
    dfinition: anything that causes RBC oxidative stressinfection (most common)oxidative drugs = antimalarials, antibiotics, antipyretics fava beans
  128. How does our body defend against ROS/RNOS?
    • AOX defense enzymes
    • Endogenous AOX
    • Dietary AOX
    • Compartmentalization- peroxisomes, metal cofactrs to prevent rnxs
    • General repair mechanissms- DNA repair, degrade and resynthesize affected proteins, removal of oxidized lipids
  129. Superoxide Dismutase
    O2. --> H202 (not toxic), releases oxygen that immediately binds to positive factors

    • cytosolic and extracellular forms require Cu+ or Zn+
    • mitocchondrial form requires Mn+
  130. Catalase
    • H2O2 --> O2 + 2H20
    • usually found in liver and kidney because thats where most peroxisomes are
  131. Glutothione peroxidase
    • H2O2 --> H2O
    • reduces peroxide into water
    • reduces lipids to alcohol
    • found in mitochonria and cytosol
  132. Uric Acid
    • Endogenous Scavenger
    • water soluble so enters plasma, saliva, and lungs to scavenge free radicals
  133. Vitamin E
    • dietary AOX
    • contains tocopherols- terminates free radical chain reactions of lipid peroxidation
    • alpha isomer acts against ROS
    • gama isomer- acts against RNOS
  134. Vitamin C
    • dietary AOX
    • regenerates the reduced form of Vitamin E
  135. Caretenoids
    gets rid of ROS with its long conjugated double bond structure
  136. Nucleic Acid Digestion
    • denatured in the stomach and absorbed by intestinal mucus cells
    • purines converted to uric acid and excreted in urine
    • pyrimadines go back into blood stream
  137. Chylomicron
    • lipoproteins that resynthesize TAGs, cholesterol, etc and released them back into the blood
    • excrete as a vesicle from the Golgi and then enter lymphatic circulation
    • ApoE- hepatic receptors that recognize chylomicrons
    • ApoCII- activates lipoprotein lipase (normally found on surface of capillaries)
  138. Conjugation of Bile Salts
    • conjugated via glycine (75%) and taurine (25%)
    • conjugation allows the formation of hydrophobic/philic sides to permit lipid digestion
    • primary bile salt: synthesized by liver (recycled)
    • secondary bile salt: synthesized by gut flora (excreted)
  139. Bohr effect
    "CADET Right!"

    • Shift to the Right, low affinit for O2 due to increase in:
    • +CO2
    • +ATP
    • +23BPG
    • +Exercise
    • +Temp

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