Extracellular Matrix (ECM) Lecture 5 PDF

Extracellular matrix (ECM) Lecture 5 Dr. Amal Ghanim Lecturer of Biochemistry, Faculty of Pharmacy, Fayoum University  Extracellular matrix (ECM) The tissues of a multicellular organism contain two main components, the cells...

Extracellular matrix (ECM) Lecture 5 Dr. Amal Ghanim Lecturer of Biochemistry, Faculty of Pharmacy, Fayoum University  Extracellular matrix (ECM) The tissues of a multicellular organism contain two main components, the cells themselves, and the material that lies between the cells. This material is called the extracellular matrix ‘ECM’. The ratio of tissue volume occupied by ECM to that occupied by cells varies 1- Artery walls- Tendons- Cartilage- Skin- Bone (Load bearing tissues) ECM: Cell 10 : 1 2- Muscles ECM : Cell 1 :10 The physical nature of the ECM varies from tissue to other Blood is fluid While, cartilage has a spongy characteristics Owing to the nature of extra cellular materials in those tissues One example of how the extracellular matrix influences tissue function can be seen in the differences between bone and the cornea of the eye. In bone, the extracellular matrix In contrast, the cornea's is thick and highly mineralized, extracellular matrix consists  Providing a tissue that is of a water-rich, transparent, hard, inflexible and opaque - flexible gel – just the thing for building a  Ideal for transmitting skeleton. light into your eye  ECM functions Space filler Mechanical support Cellular interaction for maintaining normal tissue Important For regeneration architecture. Cell proliferation control As it contain growth factors  ECM are made up of: 1-Fibrous structural proteins, 2-Proteoglycans including collagens and elastin 3- Adhesive glycoproteins include fibronectin and laminin 1-Fibrous structural proteins, including collagens and elastin  which give the ECM strength and resilience (tensile strength and recoil) 2- Proteoglycans  Serve as a ground substances in the ECM (permit compression resistance and lubrication).  Such as chondroitin sulfate, keratin sulphate…. 3-Adhesive glycoproteins include fibronectin and laminin  which attach cells to matrix 1-Fibrous structural proteins Collagen Elastin Elastin is a stretchy protein Much like a rubber band, elastin The most abundant protein in permits tissues to return to their human body original shape after they've been Tough protein fibers resistant to stretched. shearing forces Enable skin, arteries to stretch and In bone, tendons and skin recoil without tearing Dispersed as gel- like substance UV light damages elastin fibers; providing support and strength wrinkling seen in skin chronically exposed to sunlight. Collagen in wound healing In skin injury, collagen is the stuff that heals the wound by tissue remodeling through collagen synthesis and crosslinking For patients whose there collagen synthesis reduced due to:  decreased ascorbic acid required in the biosynthesis of collagen  or increased collagenases (which breaks collagen) Treated by:  Either ascorbic acid supplement  or increase the protein supplementation from meat or even amino capsules to increase collagen.  Collagen and aging As skin ages;  Collagen production slows down  Collagen fibers become rigid the strands of collagen are bind together and become thicker and more inflexible to movement  So, wrinkle formation and loss of skin firming To restore skin volume and decrease wrinkles  Collagen injection or topical plant or animal collagen creams with ascorbic acid  Anti oxidant containing products to decrease collagen damage  Retinoid containing product that inhibit collagenase  ECM are made up of: 1-Fibrous structural proteins, 2-Proteoglycans including collagens and elastin 3- Adhesive glycoproteins include fibronectin and laminin  Glycoproteins Proteoglycans Branched short chain Linear unbranched long chain carbohydrates carbohydrates Protein