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CONNECTIVE TISSUE - Coggle Diagram

- - - - LOOSE (AREOLAR)
        
        thin and sparse collagen fibers
        
        under epithelia, near glands or vessels
        
        inflammatory and immune response
        
        transient wandering cells from blood after stimuli
      - DENSE
        
        REGULAR
        
        in tendons and ligaments
        
        fibers in parallel amd densely packed for strenght
        
        little ecm
        
        example: tendons attach muscle to bone
        
        we can also find
        
        EPITENDINEUM (dense irregular ct around)
        
        ENDOTENDINEUM (less dense around fascicles)
        
        IRREGULAR
        
        sparse fibroblasts
        
        few nuclei
        
        little ground substance
  - - - SUPPORT, LOCOMOTION AND STORAGE OF CA AND P
      - COMPOSITION
        
        CELLS
        
        MATRIX
        
        ORGANIC
        
        OSTEOIDS (unmineralized bone) made of BMP (bone matrix proteins) and type 1 collagen
        
        BMP= osteocalcin, osteonectin, ALP and phosphoglucans
        
        INORGANIC (calcium phosphate in form hydroxyapatite crystals)
      - 5 TYPES OF CELLS
        
        OSTEOPROGENITOR CELLS
        
        give rise to osteoblasts by expressing RUNX2 8core binding factor alpha1 (cbfa1)
        
        OSTEOBLASTS
        
        produce and calcify bone matrix
        
        differentiation
        
        MSC can express
        
        Soxs
        
        becomes a CHONDROCYTE
        
        Runx2 (stimulated by Wnt proteins)
        
        becomes [PREOSTEOBLAST
        
        2 more items...
        
        Wnt produced when frat-1, dash and axin get to the receptor frizzled and coreceptor LRP5/6, this binding inhibits GSK3 which frees the b-catenin that migrates to the nucleus and activates TCF/LEF and produces RUNX
        
        BONE-LINING CELLS
        
        inactive osteoblasts, cover bone that is not remodelling, are also called endosteal or periosteal cells
        
        OSTEOCYTES
        
        MSC > preosteoblast > osteoblast secretes osteocalcin > osteoid osteoblast > mineralizing osteocyte (formation of dendrites and canalicoli) osteocyte secretes collagen 1
        
        Dendrites grow in canalicoli and connect osteocytes (dendrites connected by gap junctions)
        
        MECHANOTRANSDUCTION- They feel bone fluid, stress to canaliculi, to gap junctions to osteocytes that stimulates growth
        
        Produce PGE2 NO ATP that stimulate differentiation into osteoblast
        
        Produce sclerostin, DKK1 and SFRP1 inhibit osteoblast differentiation
        
        OSTEOCLASTS
        
        resorb bone matrix
        
        Hematopoietic stem cells > osteoclast progenitor cells > pre osteoclasts (expresses TRAP gene) > inactive osteoclast > active
        
        ACTIVATION
        
        1)
      - BONE AND MUSCLE CROSSTALK
        
        problems are related
        
        OSTEOPOROSIS
        
        OSTEOSARPOENIA
        
        SARCOPOENIA
        
        defective mechanotransduction causes bone resorption > fractures
        
        osteocytes =mechano-sensor antenna
    - - types
        
        ELASTIC
        
        type 2 collagen, surr by perichondrium, flexible and elastic
        
        external ear, acoustic meatus, epiglottis of larynx
        
        FIBROUS
        
        mixed tissue of hyaline and dense ct
        
        in invertebral discs, menisci of knee, tendons
        
        HYALINE
        
        in articular joints, nose, larynx..
        
        before week 8 skeleton of embryo
        
        FIBROUS MEMBRANES that undergo INTRAMEMBRANEOUS OSSIFICATION
        
        HYALINE CARTILAGE that undergoes ENDOCHONDRIAL OSSIFICATION
        
        after almost all hyaline cartilage replaced by bones, it remains only at the EPIPHYSEAL GROWTH PLATE
        
        surrounded by PERICHONDRIUM (dense CT)
      - characteristics
        
        avascular
      - made of
        
        cells (CHONDROCYTES) in lacunae
        
        CHONDROBLASTS secrete matrix and durrounded by it
        
        CHONDROCYTES embedded in lacunae
        
        chondrocytes divide and form ISOGENOUS GROUPS
        
        with active chondrocytes we can recognize 3 types of matrix
        
        CAPSULAR OR PERICELLULAR
        
        TERRITORIAL
        
        INTERTERRITORIAL
        
        ECM
        
        collagen fibers
        
        elastic fibers
        
        proteoglycans
        
        glycoproteins
      - histogenesis
        
        MSC
        
        OSTEOBLASTS
        
        CHONDROBLASTS
        
        CHONDROCYTES
        
        CALCIFICATION
      - repair
        
        INTERSTITIAL
        
        APPOSITIONAL
      - CHONDROSARCOMAS
        
        hyaline cartilage infiltrates bone marrow cavity and surrounds trabeculae
        
        malignant tumour in axial skeleton and metaphysis of proximal ends of long bones
    - - GENERALITIES
        
        viscous, slightly alkaline (7.4)
        
        7% of body weight
        
        5L in adult
      - FUNCTION
        
        directing nutrients from GI
        
        delivering waste products
        
        transporting hormones
        
        carrying o2 and co2
        
        thermoregulation and osmoregulation
      - COMPOSITION
        
        SERUM
        
        FORMED ELEMENTS
        
        PLASMA
        
        contains FIBRINOGEN (factor 1)=blood clotting element
    - - WHITE
        
        UNILOCULAR= have single lipid droplets
        
        MOBILIZATION OF TRIGLYCERIDES
        
        LOCATION
        
        SUBCUTANEOUS ADIPOSE TISSUE
        
        VISCERAL AT
        
        larger n of macrophages and T lymphocytes (M2 MACROPHAGES AND CD4+ CELLS)
        
        OBESITY
        
        adipocyte enlarges, hypoxya, cytokines call M! and CD8+ T, M1 creates crown structure, apoptosis of cell, fibers grow, fibrosis
        
        pro-inflammatory adipokines like TNF-alpha and IL6 that increase osteoclastogenesis and inhibit osteogenesis
        
        REGULTION OF ADIPOSE TISSUE
        
        2 more items...
      - BROWN
        
        THERMOGENESIS
        
        NOREPINEPHRINE, transmits nerve impulse to beta3 adrenoreceptors, beta oxidation and activation of UCP-1 (heat)
        
        LOCATION
        
        newborns
        
        back, upper spine, shoulders
        
        adults
        
        around kidney, adrenal glands, vessels, neck, back, torax
        
        highly vascularized
        
        unmyelinated nerves that give sympathetic stimulation
        
        MULTILOCULAR
        
        development
        
        MSC (mesenchymal stem cells)
        
        PPAR-y (WHITE ADYPOCY)
        
        PRDM16/PGC1 BROWNING
        
        IRSIN (protein produced by muscles during exercise) causes BROWNING
        
        Myf5+
        
        BROWN ADIPOCYTE
        
        MYOCYTE
        
        OSTEOBLASTS AND ADYPOCYTES have same precursor
        
        if we have more osteoblasts, less adipocytes
      - PINK
        
        alveolar epithelial cells in mammary gland that produce and secrete milk
      - BMAT (BONE MARROW ADIPOSE TISSUE
        
        mixed phenotype (brown and white)
        
        hematopoietic bone marrow (RAT) growing becomes adipose-rich bone marrow (YAT)
- - - - FIBROBLASTS (CTP-CONNECCTIVE TISSUE PROPER CELLS)
        
        main types
        
        polygonal shape, evident nucleus, near fibers
      - MYOFIBROBLASTS (MYOID CELLS)
        
        properties of fibroblasts and smooth muscle cells
        
        bundles of actin, myosin, alpa-smooth muscle actin
        
        fibronexus connects actin fibers to plasma membrane
        
        lacks surrounding basal lamina
        
        role after day 5 of wound healing
      - MACROPHAGES
      - ADIPOCYTES
      - MAST CELLS
        
        type of white cells for immune response
        
        cytoplasm has large basophilic granules with PERFORMED MEDIATORS
        
        HISTAMINE
        
        HEPARIN
        
        SERINE-PROTEASES
        
        EOSINOPHIL AND NEUTROPHIL CHEMOTACTIC FACTOR
        
        also NEWLY SYNTHESIZED MEDIATORS
        
        LEUKOTRIENES
        
        TUMOR NECROSIS FGACTOR
        
        INTERLEUKINS
        
        PROSTAGLANDINS
        
        MCTC (tryptase and chymase) and MCT (tryptase)
      - ADULT STEM CELLS
        
        multipotent, can differentiate into a limited range of cell types related to their tissue of origin
      - PERYCYTES
        
        perivascular cells,, they are mesenchymal stem cells
    - - LYMPHOCYTES B AND T
      - PLASMA CELLS (mature B lymp producing antibodies)
      - GRANULOCYTES
      - MONOCYTES
        
        MACROPHAGES
      - NEUTROPHILES
      - EOSINOPHILS
      - BASOPHILES
  - - - RETICULAR
        
        type 3 collagen
        
        thinner than collagen fibers
        
        stained withn PAS or SILVER STAINING METHODS
        
        support not strenght (lymphatic system, blood vessels, nerves
        
        in loose CT at boundary of CT and epithelium
        
        wound healing- give mechanical strenght
        
        reticular fibers produced by fibroblasts but exeptions
      - ELASTIC
        
        stretch and distension
        
        thinner than collagen
        
        branched and 3 dimensional
        
        produced by fibroblasts or smooth muscles within walls of vessel
        
        elastic ligaments (vertebral column and neck ligamentum) made by fibers+collagen fibers to prevent excessive stretching)
        
        stained with ORCEIN and RESORCIN-FUCHSIN
        
        2 structural components
        
        core of elastin
        
        desmosine and isodesmosine to form covalent bonds w each other
        
        hydrophobic so slide and stretch
        
        elastogenesis thanks to emilin-1
        
        surrounding network of fibrillin microfibrils (elaborated first)
      - COLLAGEN
        
        what stain
        
        EOSIN (acidic)
        
        MALLORY AZAN (aniline blue)
        
        flexible and high tensile strenght
        
        biosynthesis
        
        NUCLEUS OF FIBROBLASTS
        
        gene transcription and translation
        
        mRNA formation
        
        pro-a-chains in ribosomes
        
        RER OF FIBROBLASTS
        
        post transcriptional modification
        
        hydroxylation
        
        glycosylation
        
        triple helix formation
        
        OUTSIDE OF FIBROBLASTS (in ECM)
        
        procollagen proteinases cleave N anc C terminnus
        
        procollagen exits
        
        FIBRILLOGENESIS with cross-link
        
        type 1 fibrillogenesis
        
        FIBRILLAR CORE of type 5 and 11
        
        TYPE 1 collagen around core
        
        TYPE 2 AND 3 collagen on top of type 1
        
        type 2
        
        TYPE 2 collagen
        
        TYPE 9 collagen that anchors
        
        3 more items...
        
        COLLAGENOPATHIES (mutation in genes that encode a-chains)-gene therapy can solve
        
        OSTEOGENESIS IMPERFECTA (brittle bone disease)
        
        2 more items...
        
        SCRUVY
        
        3 more items...
        
        GOLGI OF FIBROBLASTS
        
        further processing
        
        biodegradation
        
        PROTEOLYTIC DEGRADATION
        
        outside cells thanks to MMP (membrane type metalloproteinases LIKE COLLAGENASES, GELATINASES...)
        
        PHAGOCYTE DEGRADATION
        
        macrophages remove components of ECM
        
        fibroblasts phagocyte collagen fibrils in lysosomes
    - - PROTEOGLYCANS AND GAGS
        
        GLYCOAMINOGLYCANS
        
        neg charge- basic dyes
        
        HEPARIN
        
        DERMATAN SULFATE
        
        7 GAGs
        
        HYALURONATE
        
        vitreous humour, sinovial joints
        
        NOT contain sulfate (only ones)
        
        not form proteoglycans but proteoglycan aggregates
        
        CHONDROITIN SULFATE
        
        HEPARAN SULFATE
        
        KERATAN SULFATE
        
        PROTEOGLYCANS
        
        protein core (brown) and covalentluy attached GAG chains (blue/yellow)
        
        SYNDECAN
        
        transmembrane proteoglycan
      - GLYCOPROTEINS
        
        FIBRONECTIN
        
        dimeric linked by disulfide
        
        soluble, ins, interm
        
        LAMININ
        
        binding sites of collagen 4
        
        sites for heparan sulfate, heparin, entactin, laminin
        
        TENASCIN
        
        embryogenesis, wound healing, muscolotendinous junctions, malignant tumours
        
        binding sites for fibriniogen, heparin, EGF-like growth factor
        
        TNIIA2 (from alternative splicing of tenascin) increases metastasis of colon cancer cells)
        
        OSTEOPORIN
        
        binds to osteoclasts to attach them to bone surface
        
        sequester Ca and promote calcification of ECM
      - H20 AND SMALL MOLECULE