4.proteine metabolism

Upload: barmou-amany

Post on 04-Nov-2015

24 views

Category:

Documents


0 download

DESCRIPTION

4.Prot-pl-metab

TRANSCRIPT

  • Proteinele plasmaticeProteinele plasmatice

  • Concentraia proteinelor Concentraia proteinelor plasmatice plasmatice 6060--80 g/l80 g/l

    = parametru dinamic, determinat de= parametru dinamic, determinat de: :

    Rata de sintezRata de sintez

    Volumul de distribuieVolumul de distribuie

    Rata de Rata de catabolism catabolism

  • Absorbia fierului bariera mucoasei

    Divalent Metal Transporter (DMT)

  • Valorile normale ale capacitii de fixare a fierului i a coeficientului de saturaie al transferinei

    Parametrul mol/l g/dL

    B F B F

    Capacitatea de fixare (IBC) 32 - 50 27 - 45 180 280 150 - 250

    Capacitatea de fixare total (TIBC) 54 - 72 45 - 63 300 - 400 250 - 350

    Coeficientul de saturaie 40 % 35 % 40 /dL 35 /dL

    Transportul plasmatic al Fierului rolul ceruloplasminei si Xantinoxidazei

  • Ceruloplasmina transportul Cu

    Boala Wilson degenerescena hepato-lenticular

    Ceruplasmina seric sczut Inel Kayser-Fleischer Hepatita toxic Manifestri neurologice

    recesiv autosomal 300 mutaii ale genei ATP7B (crz 13) La 35-65% din cazuri apare mutaia H1069Q (Histidina este nlocuit de Glutamin)

  • Haptoglobina - transportorul plasmatic de Hb liber

    Haptoglobina este o 2-globulin. T1/2 5 zile Leag hemoglobina eliberat n circulaie n timpul hemolizei intravasculare. Complexele haemoglobin-haptoglobin formate sunt indeprtate de sistemul reticuloendotelial (t1/2 = 90 minute), concentratia haptoglobinei plasmatice scznd (= indicator pentru hemoliza intravascular).

  • Homozygotes for the normal protein are termed Pi (protease inhibitor) MM. 1-Antitrypsin deficiency

    is most frequently due to homozygosity for the Z allele (PiZZ), this genotype having a frequency of

    about 1 in 3000. In affected individuals, plasma 1-antitrypsin concentration is reduced to between

    10% and 15% of normal. The defect is due to a single amino acid substitution, which causes the

    protein to form aggregates that cannot be secreted from the liver, and as a result, cause liver damage.

    PiMZ heterozygotes have plasma 1-antitrypsin concentrations that are about 60% of normal; there is

    probably only a very slightly increased tendency for these individuals to develop lung disease when

    compared with normal PiMM homozygotes.

    1-Antitripsina i 2-Macroglobulina

    2-Macroglobulin (=panproteinase inhibitor) is a high molecular weight protein (820 kDa) that

    constitutes approximately one-third of the 2-globulins. Its plasma concentration is increased in the

    nephrotic syndrome. Like 1-antitrypsin, 2-macroglobulin is an inhibitor of proteases, though it has a

    broader spectrum of activity.

    A1AT este un inhibitor natural de proteaze Deficitul emfizemul i hepatita nou-nscutului

  • Principalele caracteristici ale Principalele caracteristici ale proteinelor plasmaticeproteinelor plasmatice

    Funcii Denumire Migrarea EF GM (kD) Concentraia

    I.Transportori Nespecifici

    Albumina Albumin 68 35-45 g/L

    Specifici

    Prealbumina Inainte de albumin 55 200-300 mg/L

    RBP (retinol binding

    protein)

    1-globulin 21 20 60 mg/L

    Transcortina 1-globulin 56 40-80 mg/L

    Transferina -globulin 77-88 2-4 g/L

    Transcobalamina 1-globulin 1 5 mg/L

    Haptoglobina 2-globulin 100 2,5 4,5 g/L

    TBG (tiroxin binding

    globulin)

    1-globulin 61 10 30 mg/L

    ApoA 1-globuline 20-40 1,2 2,5 g/L

    ApoB 2-globuline 250, 514 0,8 -1,5 g/L

  • II. Antiproteaze SerPIN-ce

    1-antitripsina 1-globulin 54 2-3,8 g/L

    1-antichimotripsina 1-globulin 68 350-550 mg/L

    2-antiplasmina 2-globulin 70 40-80 mg/L

    Antitrombina III 2-globulin 65 200-400 mg/L

    PC Inh 2-globulin 57 3-6 mg/L

    C1 Inh 1-globulin 104 200-300 mg/L

    PAI 50 10-30 g/L

    Neserpinice

    2-macroglobulina 2-globulin 820 2,5-4 g/L

  • III. Aprare specific

    Ig G 1,2,3-globuline 130 6-16 g/L

    Ig A 1,2-globuline 140 - 420 0,7-4 g/L

    Ig M 1-globuline 900 0,4-2 g/L

    nespecific

    Factorii coagulrii -globuline variabil 4-5 g/L

    PCR (prot. C reactiv) -globulin 140 3 mg/L

    C3 -globulin 180 0,8-1,2 g/l

    IV.Funcie controversat

    1-glicoproteina acid 1-globuline 44 0,6-1 g/L

    Ceruloplasmina 2-globulin 132 300-400 mg/L

    2-microglobulina 2-globuline 11,8 2 mg/L

  • Proteinele de fazProteinele de faz acutacut Proteinele de faz acut sunt clasificate dup evoluia lor Proteinele de faz acut sunt clasificate dup evoluia lor

    nn::

    a. proteine cu a. proteine cu cretereacreterea rapid rapid (1(1--2 ore) i intens (de 2 ore) i intens (de 1010--2000 ori) a concentraiei serice: PCR (proteina C 2000 ori) a concentraiei serice: PCR (proteina C reactiv), amiloidul seric A (SAA),reactiv), amiloidul seric A (SAA),

    b. proteine cu b. proteine cu cretere mai lent cretere mai lent (24 (24 -- 48 ore) i 48 ore) i moderat (de 2moderat (de 2--5 ori): 5 ori): 11--AT, AT, 11--GPac (GPac (11--glicoproteina glicoproteina acid), haptoglobina i fibrinogenul,acid), haptoglobina i fibrinogenul,

    c. proteine cu c. proteine cu cretere lent cretere lent (2(2--3 zile) i modest 3 zile) i modest (maximum de 2 ori): Ceruloplasmina, C3, C4 i C1 Inh,(maximum de 2 ori): Ceruloplasmina, C3, C4 i C1 Inh,

    d. componenteled. componentele negative negative ale reaciei de faz acut sau ale reaciei de faz acut sau proteine anti proteine anti faz acut: albumina, prealbumina i faz acut: albumina, prealbumina i transferina transferina

  • Aspectul grafic al unor densitograme normale (a) i patologice: inflamaie acut (b); inflamaie cronic (c); ciroz (d); sindrom nefrotic

    (e); gradient monoclonal M (f)

  • Principalele caracteristici ale claselor de imunoglobuline plasmatice

    Clasa de Ig GM

    (kD) Uniti Fab Concentraie Subclase T1/2

    Ig G 150 1 2 6-16 g/l IgG 1 - 4 23

    zile

    Ig A 160 1,2 2,4 0,7-4 g/l IgA 1 - 2 5-

    zile

    Ig M 900 5 5 0,4-2 g/l ? 6

    zile

    Ig D 185 1 2 < 40 mg/l ? 3

    zile

    Ig E 200 1 2 < 0,5 mg/l ? 3 zile

    Principalele caracteristici ale claselor de imunoglobuline plasmatice

  • Concentraia proteinelor Concentraia proteinelor plasmatice 60plasmatice 60--80 g/l80 g/l

    Parametru dinamic, determinat de Parametru dinamic, determinat de trei factori principali: trei factori principali:

    rata de sintezrata de sintez

    volumul de distribuievolumul de distribuie

    rata de catabolism rata de catabolism

  • Distribuia proteinelor ntre spaiul Distribuia proteinelor ntre spaiul vascularvascular--interstiialinterstiial

    "cernerea molecular"cernerea molecular" se numete transudat: conine < " se numete transudat: conine < 30 g/l proteine 30 g/l proteine --> raport [P> raport [Ptt] lichid intersti] lichid interstiial / [Pial / [Ptt] ] ser < 0,5ser < 0,5

    Filtrul glomerular:Filtrul glomerular:

    < 150 mg proteine/24h < 150 mg proteine/24h

    < < 330 mg Alb / 24 h0 mg Alb / 24 h

    Proteinuria fiziologicProteinuria fiziologic: albumina, a: albumina, a--11--microglobulina, microglobulina, aa--11--antitripsina, antitripsina, --22--microglobulina, lizozim, microglobulina, lizozim, cistatin C, urme: IgG, acistatin C, urme: IgG, a--11--glicoproteina acid, glicoproteina acid, transferina, RBP transferina, RBP , , proteinaTammproteinaTamm--HorsfallHorsfall

  • Proteinurii patologiceProteinurii patologice

    Renale > Postrenale > Prerenale Renale > Postrenale > Prerenale Renale:Renale:

    Glomerulare (Selective / Semiselective / Glomerulare (Selective / Semiselective / Neselective); indicele de selectivitate:Neselective); indicele de selectivitate:

    = [IgG]urx[Alb]ser / [IgG]ser x [Alb] ur= [IgG]urx[Alb]ser / [IgG]ser x [Alb] ur, , n mod normal fiind < 0,2. n mod normal fiind < 0,2. TubuloTubulo--interstiialeinterstiiale

    Postrenale: sngerri, inflamaii ale TUIPostrenale: sngerri, inflamaii ale TUI Prerenale: Bence Jones, MioglobinuriePrerenale: Bence Jones, Mioglobinurie

  • ProteinorahiaProteinorahia

    0,5% din proteinemie (max 0,4 g/l):0,5% din proteinemie (max 0,4 g/l): LCR ventricular: 0,1 LCR ventricular: 0,1 0,15 g/l0,15 g/l LCR cisternal: 0,2 LCR cisternal: 0,2 0,3 g/l0,3 g/l LCR cervical: 0,1 LCR cervical: 0,1 0,15 g/l0,15 g/l LCR toracal: 0,2 LCR toracal: 0,2 0,3 g/l0,3 g/l LCR lombar: 0,3LCR lombar: 0,3--0,4 g/l0,4 g/l

    80% din proteinele prezente n mod normal n LCR , provin din 80% din proteinele prezente n mod normal n LCR , provin din ser ser transport pasiv BHE (preAlb>, Ig, Ig

  • PerturbPerturbri ale permeabilitri ale permeabilitii ii barierei HEbarierei HE

    QAlb=[Alb]LCR mg/l / [Alb] ser mg/lQAlb=[Alb]LCR mg/l / [Alb] ser mg/l

    < 10 x 10< 10 x 10--33 pot fi ntlnite n scleroza multipl, encefalita cronic pot fi ntlnite n scleroza multipl, encefalita cronic din infecia HIV, polineuropatia alcoolic, herpes zoster.din infecia HIV, polineuropatia alcoolic, herpes zoster.

    1010-- 20 x 1020 x 10--33 pot fi ntlnite n meningite virale, pot fi ntlnite n meningite virale, meningoencefalopatii cu germeni oportuniti, polineuropatia meningoencefalopatii cu germeni oportuniti, polineuropatia diabetic, infarct cerebral, atrofia cerebral.diabetic, infarct cerebral, atrofia cerebral.

    > 20 x 10> 20 x 10--33 pot apare n sindromul Guillainpot apare n sindromul Guillain--Barre, encefalitele cu Barre, encefalitele cu virus herpex simplex, bacteriene virus herpex simplex, bacteriene ((n special cu BKn special cu BK))

    Un alt indice util n diagnostic este Un alt indice util n diagnostic este Delpech Delpech Lichtblau:Lichtblau: = [IgG]LCRx[Alb]ser / [IgG]ser x [Alb] LCR= [IgG]LCRx[Alb]ser / [IgG]ser x [Alb] LCR, n mod normal fiind < 0,7. , n mod normal fiind < 0,7. Creterea acestui indice indic producie de IgG intratecal.Creterea acestui indice indic producie de IgG intratecal.

  • Tulburri ale permeabilitii BHE Tulburri ale permeabilitii BHE

    Diagrama Reiber Diagrama Reiber Felgenhauer Felgenhauer

    QIg=[IgG+IgA+IgM]LCR / QIg=[IgG+IgA+IgM]LCR / [IgG+IgA+IgM]ser[IgG+IgA+IgM]ser

    QAlb=[Alb]LCR / [Alb]QAlb=[Alb]LCR / [Alb] serser

    1 1 N x < 15 aniN x < 15 ani

    xx 15xx 15--40 ani40 ani

    xxx 41 xxx 41 60 ani60 ani

    2 perturbri ale transferului prin 2 perturbri ale transferului prin BHE, fr sintez local de IgG; BHE, fr sintez local de IgG;

    3 3 -- perturbri ale transferului prin perturbri ale transferului prin BHE, cu sintez adiional de IgG; BHE, cu sintez adiional de IgG;

    4 4 sintez local de IgG, fr sintez local de IgG, fr perturbri ale transferului prin BHE; perturbri ale transferului prin BHE;

    5 5 fr semnificaie clinic fr semnificaie clinic

  • CatabolismulCatabolismul ProteinelorProteinelor

    Proteina t1/2 n ser

    Albumina 19-21 zile

    1-antitripsina 4 zile

    Complement C3 0,5 1 zi

    Complement C4 0,5 1 zi

    Ceruloplasmina 4 10 zile

    PCR 12 24 ore

    Feritina 10 minute

    1- fetoproteina 4 zile

    Fibrinogen 3 zile

    Haptoglobina 2 4 zile

    Ig A 6- 8 zile

    Ig G 17 - 35 zile

    Ig M 5 - 7 zile

    Ig D 3 zile

    Ig E 2 zile

    Receptorul solubil al Transferinei 10 zile

    2 - Macroglobulina 4 - 7 zile

    2 - microglobulina 40 minute

    Mioglobina 15 minute

    Prealbumina 1 2 zile

    Procalcitonina 24 30 ore

    1- glicoproteina acid 5 - 6 zile

    Transferina 7 10 zile

  • Clasificarea EnzimelorClasificarea Enzimelor

    ClaseClase ReaciaReacia EnzimeEnzime

    1. Oxidoreductaze1. Oxidoreductaze A red + B ox A ox + B red A red + B ox A ox + B red Dehidrogenaze, Dehidrogenaze, PeroxidazePeroxidaze

    2.2.Transferaze Transferaze A A B + C A + B B + C A + B CC Transaminazele, Transaminazele, Hexokinaza, Hexokinaza,

    CreatinkinazaCreatinkinaza

    3. Hidrolaze3. Hidrolaze A A B + H2O A B + H2O A H + B H + B OHOH

    Tripsina, Lipaza, Tripsina, Lipaza,

    FosfatazeleFosfatazele

    4. Liaze4. Liaze A (XH) A (XH) B A B A X + B X + B HH Anhidraza carbonicAnhidraza carbonic

    5. Izomeraze5. Izomeraze A A izo Aizo A Fosfoglucomutaza, Fosfoglucomutaza,

    Triozofosfat izomerazaTriozofosfat izomeraza

    6. Ligaze6. Ligaze A + B + ATP A A + B + ATP A B + ADP B + ADP + Pi+ Pi

    Piruvat carboxilaza, Piruvat carboxilaza,

    ADN ligazaADN ligaza

  • Clasificarea EnzimelorClasificarea Enzimelor plasmaticeplasmatice

    Clasa Exemple

    1. Enzime produse/secretate activ in plasma care si desfasoara

    activitatea in plasma

    Factorii de coagulare, Plasmina, Renina, Colinesteraza, LPL, LCAT,

    Antitrombina III

    2. Enzime care ajung in mod pasiv in plasm (fiind secretate fiziologic in

    alte compartimente)

    Tripsina, Amilaza, Lipaza pancreatic, Fosfataza

    alcalin/acid, gGT

    3. Enzime cu localizare intracelular prezena lor n

    plasm semnific citoliz

    Transaminazele (GOT/AST GPT/ALT), CPK, LDH

  • Enzime utilizate n diagnosticul clinic al unor afeciuni

    EnzimaEnzima Sursa tisularaSursa tisulara Utilitate diagnostic Utilitate diagnostic ALT / GPTALT / GPT Ficat, muchi miocardic, Ficat, muchi miocardic,

    scheletic, rinichischeletic, rinichi Afeciuni hepatolitice, Afeciuni hepatolitice,

    mioliticemiolitice

    AST / GOTAST / GOT Muchi miocardic, scheletic, Muchi miocardic, scheletic, ficat, rinichi, creierficat, rinichi, creier

    Afeciuni miolitice, Afeciuni miolitice, hepatoliticehepatolitice

    LDHLDH Muchi miocardic, scheletic, Muchi miocardic, scheletic, ficat, hematiificat, hematii

    Afeciuni hepatolitice, tumori Afeciuni hepatolitice, tumori hematologicehematologice

    CKCK Muchi scheletic, miocardic, Muchi scheletic, miocardic, creiercreier

    Infarct miocardic, distrofie Infarct miocardic, distrofie muscularmuscular

    AmilazaAmilaza Pancreas, glande salivarePancreas, glande salivare Pancreatit acut, obstrucii Pancreatit acut, obstrucii biliarebiliare

    LipazaLipaza PancreasPancreas

    Pancreatit acut, obstrucii Pancreatit acut, obstrucii biliarebiliare

    GGTGGT FicatFicat Exces de alcool, hepatite, Exces de alcool, hepatite, obstrucii biliareobstrucii biliare

    Fosfataza alcalinFosfataza alcalin Osteoblati, canalicule Osteoblati, canalicule biliare, placentbiliare, placent

    Afeciuni osoase, tumori Afeciuni osoase, tumori osoase, obstrucii biliareosoase, obstrucii biliare

    Fosfataza AcidFosfataza Acid ProstatProstat Carcinom de prostatCarcinom de prostat

  • Factorii care afecteaza Factorii care afecteaza activitatea serica a enzimeloractivitatea serica a enzimelor

    Leziuni tisulare Masa esutului

    productor al enzimei

    Rata sintezei

    Rata intrrii n snge

    Activitatea seric

    Rata de ndeprtare

    Inhibitori (otrvuri organofosforice,

    inhibitori de

    colinesteraz)

    Clearance Inactivare

  • AMI AMI evolution of enzyme evolution of enzyme activity activity