aula carb 3 glicoconjugados I proteoglicanos [Modo de Compatibilidade]

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Carboidratos: estrutura eHUCFFHUCFFHUCFFHUCFF Carboidratos: estrutura e 
função de glicoconjugados I 
(proteoglicanos)H it l U i itá iH it l U i itá iH it l U i itá iH it l U i itá i (proteoglicanos)Hospital Universitário Clementino Fraga FilhoHospital Universitário Clementino Fraga FilhoHospital Universitário Clementino Fraga FilhoHospital Universitário Clementino Fraga Filho
Prof.: Vitor H. Pomin
Curso: Farmácia
Disciplina: Bioquímica FF1p q
Glicosaminoglicanos 
GlcUA
GlcNAc
IdoUA
GalNAcHexosamine:
Uronic acid:
+
or
5’ epimer
GalHexose:
Essentials of Glycobiology, Second ed. Pg 232 Fig. 16.3 
Estrutura de proteoglicanos
CSCS
HS
Biossíntese de proteoglicanos (unidade de 
ligação)ligação)
Biossíntese de condroitim sulfato (elongação e 
modificação)modificação)
Biossíntese de heparam sulfato/heparina (elongação 
e modificação)e modificação)
Domínios de heparam sulfato/heparina
Hexuronic Acid Glucosamine Combinations in disaccharides
GlcA or IdoA or 
IdoA(2S)
GlcNAc or GlcNS
or GlcNAc(6S) or 
GlcA-GlcNAc or GlcA-GlcNS
or IdoA-GlcNS or IdoA(2S)-GlcNS
GlcNS(6S) or 
GlcNS(3S)
( )
or IdoA-GlcNS(6S) or IdoA(2S)-
GlcNS(6S) or IdoA(2S)-GlcNS(3S)
Algumas evidências da importância 
dos proteoglicanos para ados proteoglicanos para a 
integridade estrutural das cartilagens
Agrecan: principal componente de cartilagensg p p p g
A remoção dos proteoglicanos reduz a rigidezA remoção dos proteoglicanos reduz a rigidez 
da cartilagem auricular do coelho
O tamanho das cadeias deO tamanho das cadeias de 
glicosaminoglicanos, os constituintes dos 
proteoglicanos, diminuem na osteoartroseproteoglicanos, diminuem na osteoartrose
A importância dos proteoglicanos para aA importância dos proteoglicanos para a 
integridade estrutural das cartilagens
Aplicação de 
pressão sobre a Remoção da pressão sobre a 
cartilagem
ç
pressão 
Ação de glicosaminoglicanos/proteoglicanos na 
coagulação sangüínea: o uso farmacológico da heparinacoagulação sangüínea: o uso farmacológico da heparina
Hexuronic Acid Glucosamine Combinations in disaccharides
GlcA or IdoA or GlcNAc or GlcNS GlcA-GlcNAc or GlcA-GlcNS
IdoA(2S) or GlcNAc(6S) or 
GlcNS(6S) or 
GlcNS(3S)
or IdoA-GlcNS or IdoA(2S)-GlcNS
or IdoA-GlcNS(6S) or IdoA(2S)-
GlcNS(6S) or IdoA(2S)-GlcNS(3S)
The blood vessel in a normal physiological condition The blood vessel in a normal physiological condition 
Tissue factor is not exposed to blood flow
Endothelial Cells
Blood Flow
HSPG
Blood Flow DSPG
Fibroblasts / Smooth Muscle Cells Tissue factor
The beginning of blood coagulationThe beginning of blood coagulation
Injury situation of a blood vessel 
Endothelial Cells
Blood Flow
HSPG
Blood Flow
Tissue factor Coagulation 
cascade
DSPG
VII
Fibroblasts / Smooth Muscle Cells
Ph i l dPh i l d tPhysical damagePhysical damage or rupture 
of atherosclerotic plaques
Tissue Factor initiates the blood coagulation cascade Tissue Factor initiates the blood coagulation cascade 
IX
Tissue Factor + VII →Tissue Factor + VII → VIIaVIIa
XXI
PROTHROMBINPROTHROMBIN
XIa
IXa
Xa
PROTHROMBIN PROTHROMBIN 
IIII
VIIIa
Va
THROMBINTHROMBIN
VIII
V
XIII
IIaIIa
FIBRINOGEN FIBRIN CROSS LINKED
XIIIa
FIBRINOGEN FIBRIN FORMES A CLOT
The clottingThe clotting
Fibrin polymerization
Endothelial Cells
Blood Flow Fibrinogen
HSPG
Blood Flow IIa
Fibrin
DSPG
Fibroblasts / Smooth Muscle Cells
The thrombusThe thrombus
The common pathological situation in thromboembolism
Endothelial Cells
Blood Flow Fibrinogen IIaDSPG
HSPG
Blood Flow
Fibrin
IIa
Thrombus
IIa
Fibroblasts / Smooth Muscle Cells
The haemostasisThe haemostasis
A balance between Pro- and Anticoagulant-factors
Tissue Factor + VII →Tissue Factor + VII → VIIaVIIa
IX X
XI
IXa
PROTHROMBIN IIPROTHROMBIN II
XIa
Heparin 
Xa
XIII
VIII
VIIIa
Va
Cofactor II
XIII
THROMBINTHROMBIN
IIaIIa
V
ANTITHROMBIN
FIBRINOGEN FIBRIN CROSS LINKEDFORMES A CLOT
XIIIa
ANTITHROMBIN
The inhibitors will be amplifiedThe inhibitors will be amplified
The role of the proteoglycans (HSPG and DSPG) and soluble heparin
Tissue Factor + VII →Tissue Factor + VII → VIIaVIIa
IX X
XI
IXa
PROTHROMBIN IIPROTHROMBIN II
XIa
Heparin 
Xa
XIII
VIII
VIIIa
Va
p
Cofactor II
(Amplified by DSPG or HEPARIN)
XIII
THROMBINTHROMBIN
IIaIIa
V
ANTITHROMBIN
FIBRINOGEN FIBRIN CROSS LINKEDFORMES A CLOT
XIIIa
ANTITHROMBIN
(Amplified by HSPG or HEPARIN)
The haemostasisThe haemostasis
Pro- and anticoagulant systems
Endothelial Cells
Blood Flow Fibrinogen AnticoagulantAnticoagulant
ATIIa
heparin
IIa
AT
HSPG
Blood Flow IIa
ATIIa HCIIIIa
AnticoagulantAnticoagulant
ProcoagulantProcoagulant
p
AT
Fibrin
Fibroblasts / Smooth Muscle Cells
The inhibition mechanisms of heparinThe inhibition mechanisms of heparin
T diff t h iTwo different mechanisms
Accessible arginine on reactive siteAccessible arginine on reactive siteAccessible arginine on reactive siteAccessible arginine on reactive siteAllostericAllosteric
AT AT
a
AT AT
a
AT AT
a
AT ATa HEP
AllostericAllosteric
aaa P-Pentasac
TemplateTemplate
charide
AT
IIa
pp
Heparin-18 residues
GAGs on inflammation process 
CCL5/RANTES (Regulated upon Activation Normal T cellCCL5/RANTES (Regulated upon Activation, Normal T-cell
Expressed and Secreted) is a member of the CC-chemokines
(chemotactic cytokines)( y )
40’s loop
CCL5
(aa 43-48) Vangelista et al. Vaccine 2008
H i bidi itCCL5
MW ~ 8 KDa (68 aa)
Physiologically associated as dimers
Heparin-biding site
Region BBXB
(44RKNR47)( RKNR )
Proutfoot et al. JBC 2001
3. INTRODUCTION
CCL5/RANTES the GAG chemokine interactions play role on activation andCCL5/RANTES – the GAG-chemokine interactions play role on activation and
migration processes of certain leukocytes (T-cells, eosinophils, and basophils)
GAG-chemokine in gradient formation:
1. selectin-mediated rolling;
2. leukocytes activation by chemokines;
3. integrin-induced arrest / 
morphological change;
4. transmigration (extravasation) 
Handel et al. Annu. Rev. Biochem. 2005
3. INTRODUCTION
CCL5/RANTES the physiological GAG induced chemokine multimerizationCCL5/RANTES – the physiological GAG-induced chemokine multimerization
create a high local concentration of chemokines (chemoattraction of cells for injury sites);
increase the in vivo chemokines half-life (protection from natural proteolysis);
promote resistance to disruption by blood flow in the vessels;
may also serve as storage forms for rapid mobilization of chemokines without biosynthesis.may also serve as storage forms for rapid mobilization of chemokines without biosynthesis.