biochem2 Flashcards
Which cells produce collagenase in HEALTH?
Fibroblasts
Which cells produce collagenase in DISEASE?
polymorphonucleocytes macrophages
Some bacteria can also secrete collagenase
Name the enzyme that breaks down collagen
Collagenase
What type of enzyme is collagen?
It is a matrix metalloprotease (MMP)| It is an Endopeptidase
What link has been suggested between TIMP and periodontal disease?
there has been some suggestion that TIMP may be downregulated in certain patients tipping the balance towards periodontal breakdown.
How much faster is collagen synthesis in PDL compared to subdermal gingiva?
2 times
How much faster is collagen synthesis in PDL compared to Skin
4 times faster
How much faster is collagen synthesis in PDL compared to Alveolar bone?
6 times fater
How much faster is collagen breakdown in PDL compared to the gingiva?
5 time faster
How much faster is collagen breakdown in PDL compared to skin?
15 times faster
How much faster is collagen breakdown in PDL compared to alveolar bone
6 times faster
What is the half life of collagen in the PDL, gingiva and skin
PDL: 40 minsGingiva: 80 minsSkin: 360 mins
What model can we use to help us understand disease progrssion within the periodontal ligament ?
By using sheep
What do some sheep suffer from?
A condition called broken moth
What is broken mouth clinical similar to?
To rapidally progressing periodontitis in men
What happens ti sheep suffering from broken mouth?
Their quickly lose their lower teeth
What happen to the amount of collagen in sheep suffering from broken mouth?
there was an overall loss of collagen from the gingiva and periodontal ligament with disease
What happens to the activity of gelatinase in sheep suffering from broken mouth?
There was an increased activity of the enzymes in the diseased tissue
What 3 things did scientist look at in sheep with broken mouth disease?
Gelatinase enzyme activity Collagen levels GCF was tested
What were scientist looking fro when they tested the GCF of disease sheep?
looked for evidence of any collagen fragments that might be present in the sulcus
What was the underlying hypothesis scientists were working around when they were looking at sheep with broken mouth disease?
The underlying hypothesis was that if there is increased collagen degradation occurring during episodes of active periodontal disease, then some of those fragments might “wash out” in to the gingival crevice due to the increase fluid outflow that occurs with gingival inflammation.
What did southern blotting of the GCF in sheep with broken mouth disease show?
detected fragments of collagen in the crevicular fluid of diseased animals but not in healthy animals.
Has a strong correlation between PDL conditions in sheep with broken mouth disease and humans with periodontitis been found?
No a strong correlation has not been found
Where is the ground substance found?
It is present as the cement around the fibres in all connective tissues, including periodontal ligament
What does the ground substance comprise of?
- Non-collagenous proteins (NCPs)2. Hyaluronic Acid (GAG)3. Proteoglycans (PGs)
Give an example of a non collagenous protein?
fibronectin which is a glycoprotein
What are proteoglycans made up of?
Proteoglycans are monomers made up of a protein core to which is covalently bonded to a chain(s) of glycosylaminoglycans (GAGs)
What are glycosylaminoglycans?
GAGs are carbohydrate heteropolymers, made up of repeating disaccharide sub-units. Each disaccharide sub-unit is comprised of a hexosamine sugar plus a uronic acid residue
Are glycosylaminoglycans hydrophilic or hydrophobic?
They are highly HYDROPHILIC and attract and bind many water molecules as part of their extended structure