Salivary Proteins

Front 1

What are the implications of the demographic change that can challenge dentistry and saliva issues?

Back 1

*Increasing elderly=
1. Increase in diseases affecting salivary glands (Sjogrens, autoimmune diseases, head/neck cancer)
2. Increase in medication use with salivary effects.
EG:
*Anticholinergics (antihistamines, antidepressants)-these have a direct/indirect effect on proteins
*Beta adrenergic agonists and antagonists that have a DIRECT effect on protein synthesis/secretion
(asthma, hypertension, cardiovascular disease)

Front 2

What are the current products out there containing saliva proteins?

Back 2

1. Biotene (peroxidase, lysozyme lactoferrin)
2. Histatin rinses/gels

Front 3

Name the origins of salivary proteins, where do the secretions come from?

Back 3

1. Serous acinar-Parotid (little SM/SL)
-ions, water, proteins
2. Mucous acinar-SM/SL and minor glands-complex glycoproteins
3. Duct cells-differs among glands
(proteins emphasized in different glands)
4. Immune system cells-B cell (S-IgA) translocated to ducts, Neutrophils have indirect leakage into gingival crevice
5. Leakage from gingival fluid contributes serum proteins (WS only)
6. Oral epithelial cells release surface proteins (whole saliva only)

Front 4

What are the 3 ways that salivary proteins protect tissues? What bacteria do so?

Back 4

1. Pellicle formation:(9)
Statherin, aPRP, amylase, histatins, cystatins, MUC7 mucin, lysozyme, albumin, carbonic anhydrase

2. Lubrication:
Statherin, MUC5B mucin (also reflux protection)

3. Maintain saliva calcium in equilibrium with enamel:
(saliva is supersaturated with Ca2+ and Phosphate and precipitation must be prevented)
-Statherin, aPRP, histatins, cystatins

Front 5

Saliva functions as food processing, how so?

Back 5

1. Amylase-initial starch breakdown
2. Binding/detoxification of dietary tannins
(aPRP, basic PRP, histatins)
3. Protein processing-Kallikrein and other proteases
4. Swallowing-MUC5B

Front 6

Saliva manages microbes via antimicrobial functions (bacteria, fungi, viruses) by what means?

Back 6

1. Direct-killing
(histatins, lysozyme, amylase, MUC7, lactoferrin, defensins, peroxidase)

2. Indirect-inhibition of infectivity, microbial metabolism, bacterial/viral proteases (lactoferrin, cystatins, histatins, basic PRP, SLIPI, peroxidase, S-IgA)

3. Aggregation-bind to microbes, clear with swallowing
(MUC7, lysozyme, lactoferrin, glycosylated PRP, parotid agglutinin, extra-parotid gylcoprotein, S-IgA

Front 7

What protein does the microbes manage in metabolism?

Back 7

MUC5B

Front 8

What is the term given to describe how most saliva proteins have actions that help the host and others that seem to help microbes?

Back 8

*Amphifunctional

They also can be mediated by different domains

Front 9

What is the term to describe how many proteins share similar functions and name them.

Back 9

*Redundancy
These multiple gene families have 2-4 closely linked genes coding very similar proteins
(aPRP, bPRPR, gPRP, cystatins, histatins, amylase, MUCs)
They have multiple alleles for each gene.

Front 10

Name some salivary proteins that are cleaved by proteases during secretion in the mouth.

Back 10

*aPRP, bPRP, gPRP, histatins, S-IgA

The fragments may function differently together than they do alone

Front 11

Proteins function differently together than they do alone, list the 3.

Back 11

Lysozyme, Lactoferrin, peroxidase

Front 12

Salivary proteins bind in a large heterotypic complex that function differently than component proteins. List them

Back 12

MUC5B, amylase, aPRP, S-IgA, peroxidase, lysozyme, lactoferrin, statherin

Front 13

Characteristics of Statherin.

Back 13

-multiple gene family
-small tyrosine-rich phosphoproteins
-negatively charged Calcium binding N-terminal (2 phosphoserines-add'l neg. charges, maintains calcium balance and strongly prevents precipitation)
-Binds tooth surfaces and changes conformation (bulky tyrosine rich c terminal, lubrication of tooth (pellicle), adherence of Actinomyces species.

Front 14

Characteristics of aPRP.

Back 14

-proline-rich phosphoproteins
(negatively charged calcium binding n-terminal, 2 phosphserines, calcium balance, strongly prevents participation)
-Binds tooth surface-changes conformation (c-terminal rich in bulky prolines and adherence of streptococcus species (pellicle))
-proteases cleave n-terminal from c-terminal and the free c-terminal binds tannins; blocks bacterial adhesion

Front 15

Characteristics of Histatins.

Back 15

-largest is phosphoprotein
-small peptides after proteolysis (positive charge-histadine-rich
-microbial cell damage-antibacterial, anti-fungal (also calcium balance, tannin binding, protease inhibitor
-clinical interest-safe