This document summarizes the major salivary enzymes and their functions. It begins by outlining the chronological discovery of salivary components starting in the 1950s. It then describes the current understanding of salivary proteins' structure-function relationships and conformational requirements. The document discusses the expected network action of the salivary defense system and lists the five primary defense networks involving proteins that agglutinate bacteria, lyse bacterial membranes, and have antifungal and antiviral properties. Finally, it provides details on specific salivary components like defensins, histatins, lactoferrin, and lysozymes that have antimicrobial functions.
Definition
Classification Of Salivary Glands
Anatomy of salivary glands
Development of salivary glands
Structure Of Salivary Glands
Histology of major and minor salivary glands
This Presentation includes systematic compilation of the anatomy, physiology, biochemistry and pathology related to saliva and salivary glands. it also mentions about the role of saliva in dentistry. Any additions or mistakes are welcome!
Please do leave your comments and let me know if the presentations has helped you!
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Central face begins to develop by 4th week, when olfactory placodes appear on both sides of the frontonasal process.
Gradually both placodes develop to form the median and lateral nasal process.
Upper lip is formed by 6th week by fusion of two median nasal processes in midline and the maxilllary process of the 1st branchial arch.
PRE-NATAL GROWTH AND DEVELOPMENT OF PALATEFormation of primary and secondary palate
Elevation of palatal shelves
Fusion of palatal shelves
Introduction
Prevention of caries
Brief introduction about types of Immunity
Causative factors of dental caries
Virulance of S mutans
Natural immune barriers
Salivary secretion and its composition
Natural barriers
Innate immune responses of dental pulp to caries
Acquisition of oral microbes
Factors affecting oral microbial colonization
Innate salivary factors found in oral cavity
Adaptive immunity
Secretary IgA
Types of Immunization
Routes of Immunization
Conclusion
Amelogenesis is the formation of enamel. During amelogenesis, the ameloblast (enamel-forming cells) undergo various stages i.e the life cycle of ameloblast.
For more content check out my blog: www.rkharitha.wordpress.com "a little about everything dental"
Coronal and radicular pulp
Apical foramen
Accessory canal
Functions of dental pulp
Components of dental pulp
Functions of pulpal extracellular matrix
Organization of cells in the pulp
The principle cells of the pulp
The pathways of collagen synthesis
Matrix and ground substances
Vasculature and lymphatic supply
Innervation of Dentin- pulp complex
Disorders of the dental pulp
Advances in pulp vitality testing
Definition
Classification Of Salivary Glands
Anatomy of salivary glands
Development of salivary glands
Structure Of Salivary Glands
Histology of major and minor salivary glands
This Presentation includes systematic compilation of the anatomy, physiology, biochemistry and pathology related to saliva and salivary glands. it also mentions about the role of saliva in dentistry. Any additions or mistakes are welcome!
Please do leave your comments and let me know if the presentations has helped you!
The presentation is available on request. Mail me at apurvathampi@gmail.com
Central face begins to develop by 4th week, when olfactory placodes appear on both sides of the frontonasal process.
Gradually both placodes develop to form the median and lateral nasal process.
Upper lip is formed by 6th week by fusion of two median nasal processes in midline and the maxilllary process of the 1st branchial arch.
PRE-NATAL GROWTH AND DEVELOPMENT OF PALATEFormation of primary and secondary palate
Elevation of palatal shelves
Fusion of palatal shelves
Introduction
Prevention of caries
Brief introduction about types of Immunity
Causative factors of dental caries
Virulance of S mutans
Natural immune barriers
Salivary secretion and its composition
Natural barriers
Innate immune responses of dental pulp to caries
Acquisition of oral microbes
Factors affecting oral microbial colonization
Innate salivary factors found in oral cavity
Adaptive immunity
Secretary IgA
Types of Immunization
Routes of Immunization
Conclusion
Amelogenesis is the formation of enamel. During amelogenesis, the ameloblast (enamel-forming cells) undergo various stages i.e the life cycle of ameloblast.
For more content check out my blog: www.rkharitha.wordpress.com "a little about everything dental"
Coronal and radicular pulp
Apical foramen
Accessory canal
Functions of dental pulp
Components of dental pulp
Functions of pulpal extracellular matrix
Organization of cells in the pulp
The principle cells of the pulp
The pathways of collagen synthesis
Matrix and ground substances
Vasculature and lymphatic supply
Innervation of Dentin- pulp complex
Disorders of the dental pulp
Advances in pulp vitality testing
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
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Antimicrobial Defense System in Saliva, Antioxidant Role of Saliva, Maintenance of pH, Maintenance of Mucous Membrane Integrity, Maintenance of Ecological Balance, Maintenance of Tooth Integrity, Debridement & Lavage, Soft Tissue Repair, Saliva & Dental Caries, As Diagnostic Marker.
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S. mutans was originally isolated from carious human teeth by Clarke in 1924.
Little attention was paid to this species until the 1960s when it was demonstrated that caries could be experimentally-induced and transmitted in animals artificially-infected with strains resembling S. mutans.
Besides functioning as a resistant structural matrix, insoluble extracellular polysaccharides can act as a diffusion barrier.
The transport of metabolites and salivary buffers into the plaque and the diffusion of acid out of the plaque may be affected by glucan.
Fructans, on the other hand, unlike the mutan homopolymer of glucan, are generally soluble and can be degraded by plaque bacteria, thus serving as a reservoir of fermentable sugars for oral bacteria.
A group of fructans produced by bacteria or created by breaking down other kinds of plant fructans are called levan .
Levans are both more soluble and more readily catabolized than glucans.
Since levan hydrolysis is rapid, it may function as a short-term reservoir for the sustenance of bacterial anaerobic glycolysis in times of relative unavailability of dietary carbohydrate.
Lipoteichoic acid is another extracellular polymer that is found in cultures of S. mutans. These highly negatively charged compounds might contribute to the adhesiveness of bacteria.
In addition to this, S. mutans strains have an ability to store intracellular glycogen amylopectin type polysaccharide, which provides a reservoir of substrate and enables prolonged periods of increased metabolic activity.
Intracellular glycogen and extracellular polysaccharides serve as substrate reservoirs, which the organism may utilize for energy production, as the exogenous supplies of readily metabolized carbohydrate are depleted. In this fashion, both types of polysaccharides may play a role in the survival of organisms and in their potential to prolong acid production via glycolysis well beyond meal time.
It is known that sucrose-adapted S. mutans strains possess significant levels of invertase activity, and this enzyme isknown to hydrolyze sucrose intracellularly to free glucose and fructose.
Invertase is activated by inorganic phosphate and since phosphate accumulation is coupled with acid production, it is probable that one of the several mechanisms by which sucrose degradation is regulated in S. mutans is the activation of invertase by inorganic phosphate.
Cariogenic features of mutans streptococci - Binding to and colonization of teeth
Accumulation on tooth surfaces & participation in the formation of dental plaque.
Production of acid at a high rate.
Tolerance of high concentration of sugar, high ionic strength & highly acidic conditions
Association with dental caries in humans
Causation of dental caries in animals
Transmissible in animals & apparently in man
Reduction or elimination of mutans results in reduction or elimination of dental caries
antimicrobial peptides are class of biological defense molecules which act as a part of our innate immune system.in oral cavity any microbial insult will be resisted by physical,biological and chemical barrier there by maintaining oral homeostasis.these molecules are of low molecular weight with less than 100 amino acids. main antimicrobial peptides include defensin,histatin,cathelicidin and statherin etcc.they develop resistence very slowly,prvrnt biofilm formation and in future they can be used as therapeutic agents
The dimensions of healthcare quality refer to various attributes or aspects that define the standard of healthcare services. These dimensions are used to evaluate, measure, and improve the quality of care provided to patients. A comprehensive understanding of these dimensions ensures that healthcare systems can address various aspects of patient care effectively and holistically. Dimensions of Healthcare Quality and Performance of care include the following; Appropriateness, Availability, Competence, Continuity, Effectiveness, Efficiency, Efficacy, Prevention, Respect and Care, Safety as well as Timeliness.
Medical Technology Tackles New Health Care Demand - Research Report - March 2...pchutichetpong
M Capital Group (“MCG”) predicts that with, against, despite, and even without the global pandemic, the medical technology (MedTech) industry shows signs of continuous healthy growth, driven by smaller, faster, and cheaper devices, growing demand for home-based applications, technological innovation, strategic acquisitions, investments, and SPAC listings. MCG predicts that this should reflects itself in annual growth of over 6%, well beyond 2028.
According to Chris Mouchabhani, Managing Partner at M Capital Group, “Despite all economic scenarios that one may consider, beyond overall economic shocks, medical technology should remain one of the most promising and robust sectors over the short to medium term and well beyond 2028.”
There is a movement towards home-based care for the elderly, next generation scanning and MRI devices, wearable technology, artificial intelligence incorporation, and online connectivity. Experts also see a focus on predictive, preventive, personalized, participatory, and precision medicine, with rising levels of integration of home care and technological innovation.
The average cost of treatment has been rising across the board, creating additional financial burdens to governments, healthcare providers and insurance companies. According to MCG, cost-per-inpatient-stay in the United States alone rose on average annually by over 13% between 2014 to 2021, leading MedTech to focus research efforts on optimized medical equipment at lower price points, whilst emphasizing portability and ease of use. Namely, 46% of the 1,008 medical technology companies in the 2021 MedTech Innovator (“MTI”) database are focusing on prevention, wellness, detection, or diagnosis, signaling a clear push for preventive care to also tackle costs.
In addition, there has also been a lasting impact on consumer and medical demand for home care, supported by the pandemic. Lockdowns, closure of care facilities, and healthcare systems subjected to capacity pressure, accelerated demand away from traditional inpatient care. Now, outpatient care solutions are driving industry production, with nearly 70% of recent diagnostics start-up companies producing products in areas such as ambulatory clinics, at-home care, and self-administered diagnostics.
ICH Guidelines for Pharmacovigilance.pdfNEHA GUPTA
The "ICH Guidelines for Pharmacovigilance" PDF provides a comprehensive overview of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines related to pharmacovigilance. These guidelines aim to ensure that drugs are safe and effective for patients by monitoring and assessing adverse effects, ensuring proper reporting systems, and improving risk management practices. The document is essential for professionals in the pharmaceutical industry, regulatory authorities, and healthcare providers, offering detailed procedures and standards for pharmacovigilance activities to enhance drug safety and protect public health.
Antibiotic Stewardship by Anushri Srivastava.pptxAnushriSrivastav
Stewardship is the act of taking good care of something.
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
WHO launched the Global Antimicrobial Resistance and Use Surveillance System (GLASS) in 2015 to fill knowledge gaps and inform strategies at all levels.
ACCORDING TO apic.org,
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
ACCORDING TO pewtrusts.org,
Antibiotic stewardship refers to efforts in doctors’ offices, hospitals, long term care facilities, and other health care settings to ensure that antibiotics are used only when necessary and appropriate
According to WHO,
Antimicrobial stewardship is a systematic approach to educate and support health care professionals to follow evidence-based guidelines for prescribing and administering antimicrobials
In 1996, John McGowan and Dale Gerding first applied the term antimicrobial stewardship, where they suggested a causal association between antimicrobial agent use and resistance. They also focused on the urgency of large-scale controlled trials of antimicrobial-use regulation employing sophisticated epidemiologic methods, molecular typing, and precise resistance mechanism analysis.
Antimicrobial Stewardship(AMS) refers to the optimal selection, dosing, and duration of antimicrobial treatment resulting in the best clinical outcome with minimal side effects to the patients and minimal impact on subsequent resistance.
According to the 2019 report, in the US, more than 2.8 million antibiotic-resistant infections occur each year, and more than 35000 people die. In addition to this, it also mentioned that 223,900 cases of Clostridoides difficile occurred in 2017, of which 12800 people died. The report did not include viruses or parasites
VISION
Being proactive
Supporting optimal animal and human health
Exploring ways to reduce overall use of antimicrobials
Using the drugs that prevent and treat disease by killing microscopic organisms in a responsible way
GOAL
to prevent the generation and spread of antimicrobial resistance (AMR). Doing so will preserve the effectiveness of these drugs in animals and humans for years to come.
being to preserve human and animal health and the effectiveness of antimicrobial medications.
to implement a multidisciplinary approach in assembling a stewardship team to include an infectious disease physician, a clinical pharmacist with infectious diseases training, infection preventionist, and a close collaboration with the staff in the clinical microbiology laboratory
to prevent antimicrobial overuse, misuse and abuse.
to minimize the developme
CHAPTER 1 SEMESTER V PREVENTIVE-PEDIATRICS.pdfSachin Sharma
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Leading the Way in Nephrology: Dr. David Greene's Work with Stem Cells for Ki...Dr. David Greene Arizona
As we watch Dr. Greene's continued efforts and research in Arizona, it's clear that stem cell therapy holds a promising key to unlocking new doors in the treatment of kidney disease. With each study and trial, we step closer to a world where kidney disease is no longer a life sentence but a treatable condition, thanks to pioneers like Dr. David Greene.
CRISPR-Cas9, a revolutionary gene-editing tool, holds immense potential to reshape medicine, agriculture, and our understanding of life. But like any powerful tool, it comes with ethical considerations.
Unveiling CRISPR: This naturally occurring bacterial defense system (crRNA & Cas9 protein) fights viruses. Scientists repurposed it for precise gene editing (correction, deletion, insertion) by targeting specific DNA sequences.
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Gene Therapy: Correcting genetic diseases like cystic fibrosis.
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Eugenics: Misusing CRISPR for designer babies raises social and ethical questions.
Equity: High costs could limit access to this potentially life-saving technology.
The Path Forward: Responsible development is crucial:
International Collaboration: Clear guidelines are needed for research and human trials.
Public Education: Open discussions ensure informed decisions about CRISPR.
Prioritize Safety and Ethics: Safety and ethical principles must be paramount.
CRISPR offers a powerful tool for a better future, but responsible development and addressing ethical concerns are essential. By prioritizing safety, fostering open dialogue, and ensuring equitable access, we can harness CRISPR's power for the benefit of all. (2998 characters)
Telehealth Psychology Building Trust with Clients.pptxThe Harvest Clinic
Telehealth psychology is a digital approach that offers psychological services and mental health care to clients remotely, using technologies like video conferencing, phone calls, text messaging, and mobile apps for communication.
Explore our infographic on 'Essential Metrics for Palliative Care Management' which highlights key performance indicators crucial for enhancing the quality and efficiency of palliative care services.
This visual guide breaks down important metrics across four categories: Patient-Centered Metrics, Care Efficiency Metrics, Quality of Life Metrics, and Staff Metrics. Each section is designed to help healthcare professionals monitor and improve care delivery for patients facing serious illnesses. Understand how to implement these metrics in your palliative care practices for better outcomes and higher satisfaction levels.
1. Salivary enzymes & Their functions
Presented by
Roshni Maurya
Dept.of Pediatric & Preventive Dentistry
2. Chronology of defining salivary components and functions
Beginning in 1950’s whole saliva evaluated (antimicrobial properties,
role in microbial attachment, mineralization, taste, lubrication)
Secretions of major glands (parotid and submandibular/sublingual)
In 1970’s individual components isolated and biochemically
characterized
In mid-1980’s beginning to map functional domains (peptide synthesis
and recombinant approaches)
3. CURRENT CONCEPTS REGARDING THE FUNCTIONAL FEATURES OF SALIVARY
MACROMOLECULES
Recent structure/function studies have identified general principles
regarding function
Based on in vitro studies of purified molecules
Additional studies required to evaluate concepts in situ
Conformational requirements
Conformation or shape of a molecule is critical for its biological function
Examples
Proline-rich proteins interact with A. viscosus and St. gordonii only when
adsorbed onto mineralized surface
Statherins and histatins require -helical conformation
Human salivary amylase require 5 inter-chain disulfide bonds
4. EXPECTED NETWORK ACTION OF THE SALIVARY DEFENSE
SYSTEM
Salivary defense proteins may enrich concentrations to “efficient” levels in certain locations in
the oral cavity, notwithstanding that many of them are found in whole saliva in less than- efficient
concentrations.
In these locations, a “single-hit” type of action (one type of agent affects the target) of salivary
defense proteins may occur.
Salivary proteins(including cationic peptides) may also provide antimicrobial defense, even if
they are present in concentration that are lower than efficient.
In such case, a network type “multihit” approach may be expected. Several kinds of salivary
defense proteins affect the targeted microbe at the same time.
Although, a certain salivary protein may induce a “partial knockout” of targeted microbe only,
their network type “acting together” at same time may lead to efficient elimination of the target.
5. EXPECTED FIVE PRIMARY DEFENSE NETWORKS OF SALIVARY
PROTEINS
PROTEINS IN WHOLE SALIVA
First network may be responsible for microbial agglutination and/or surface exclusion. This
may include those salivary proteins and peptides which bind bacteria (microbes) and also
bind to either oral surfaces or each other or both.
2nd network may be expected to be responsible for lysis of microbial membranes. This
primarily targets bacteria, includes salivary cationic peptides and lysozyme.
Third and Fourth networks may be responsible for antifungal and antiviral properties of
saliva respectively.
Finally, a fifth, immune regulatory network of salivary proteins may be expected. This
includes all those salivary proteins exerting immune activator/modulator properties. It may
be important for fine-regulation of local action of mucosal immune system.
7. SALIVARY ANTIBODIES
MAJOR CLASSES OF SALIVARY ANTIBODIES
Salivary antibodies act in first line of defense by performing immune exclusion of antigen in : saliva; mucus
layer on epithelial surfaces; acquired pellicle on tooth surface.
They are constitutively excreted into saliva and oral cavity.
2 major classes in human saliva :a) secretory IgA-its main source is salivary gland ;in less amt.secreted by
mucosal cell; ,is dimeric,may be polymeric.
The other is IgG- monomeric,either serum derived or produced by local plasma cells.
Although majority of Abs belong to IgA(90-98%); IgG (1-10%) classes small fractions of IgM ,IgE Abs are
present in saliva as well.
Serum derived IgG and monomeric IgA enters oral cavity via: GCF(mainly); mucosal transudate;
ultrafiltration through salivary gland acini.
8. PRODUCTION OF SALIVARY SECRETORY ANTIBODY
Intial stimulation of secretory Ig expressing B-cells takes place in MALT,such as GALT and
NALT.
Salivary secretory namely sIgA and very small amt. of sIgM are produced by specific plasma cells
residing primarily in salviary gland storma and in small nos. in o.mucosa.
The plasma cell release mainly dimeric; some polymeric IgA molecules and few pentameric IgM
molecules.
These Ig are exported to saliva by acinar cells;ductal cells of minor and major sal.gland via a
common sal.gland epithelial transport mechanism.
9. ANTIGEN BINDING;AGGLUTINATION AND SURFACE EXCLUSION:
Pri.function of sal.(secretory and other)Ig is to inactivate parasites-bacteria;fungi;viruses via binding/or
agglutination of such particles.
Surface immune exclusion of pathogen within o.cavity via anchorage of secretory Ig- binding antigens to
the superficial mucous layer lining mucosal surface –another imp. mechanism to prevent invasion of
underlying tissues.
PHAGOCYTOSIS;ANTIGEN PRESENTATION;DEGRANULATION AND CYTOKINE PRODUCTION:
Oral mucosal surface is extensively populated by antigen presenting cells(Langerhans and dendrictic
cells);there is a considerable flux of neutrophil granulocytes through gingival sulcus into the saliva even in
the healthy. As both dendrictic and neutro.graulocytes have immune activating IgA activating receptors on
their surface, premised immune –cell coupled defense functions of sal.IgA and others are likely to be active
to maintain immune surveillance.
ANTIBODY CATALYZED OZONE FORMATION:
In the presence of reactive oxy.int.(ROI)- producing neutro.gran.;sal.Abs can catalyze ozone formation
leading to efficient microbial killing. During this process, Abs kill microbes by catalytically converting a
less toxic ROI to a mixture of hydrogen peroxide and ozone.
10. SALIVARY CHAPEROKINE HSP70/HSPAS
Salivary glands are among the main sources of HSP70/HSPAs in saliva.Besides sal.glands other
imp.sources are mucosal cells,GCF,oral mucosal cells,intra oral bleeding(bleeding periodontal
pockets,wounds,ulcers)
BINDING OF BACTERIA,AGGLUTINATION AND SURFACE EXCLUSION:
Sal.HSP70/HSPAs may entrap and agglutinate bacteria. Recent data has indicated that the this
proteins bind both gram+ve( Strepto.mutans;mitis) and gram-ve (E.coli) bacteria.
IMMUNOLOGICAL DEFENSE MECHANSIMS:
3 major facets of immune activation are described:
First involves extracellular second involves complexes of third exert an opsonizing
HSP70/HSPA as an ancestral extracellular HSP70/HSPA proteins effect on bacteria activating
danger signal of cellular stress and other peptides. Is imp. In defense the killing activity of PMNS
death or lysis. Against bacteria, tumor cells, neutrophil granulocytes,
virus infected cells. Effective under inflammatory
conditions, in case of oral lesions
11. CATIONIC PEPTIDES
DEFENSINS
‘Prototype’of cationic peptides.
Characterized by a “ hairpin-like” globular structure stabilized by three intramolecular
disulfide bridges linking six cysteine aminoacids.
Based on pattern of cystein pairing , 2 types :-
Alpha-defensins.
Beta- defensins.
Salivary Alpha-defensins (HNP1, HNP2, HNP3, HNP4) are produced by neutrophil
granulocytes .
Salivary Beta- defensins (hBD1, hBD2, hBD3, hBD4) are produced by mucosal cells.
Beside whole saliva, both Alpha- and Beta- defensins are also present in GCF. Both show
broad antibacterial activity.
12. These absorb via electrostatic forces onto negatively-charged bacterial cell membrane leading
to their subsequent aggregation and integration into lipid bilayer. Hence,
Integration of Defensins into bacterial membranes.
causes
Formation of ion channels, transmembrane pore
results
membrane leakage and rupture
Destruction of bacteria
Beside their broad antibacterial activity, they also exert antifungal and antiviral properties,
exert various immune activator and modulatory activities.
13.
14. HISTATINS
HISTATINS are small histidine-rich cationic peptide ranging in size from 7 to 38 aa.
Secreted by parotid gland, sublingulal and submandibular glands.
Imp. histatins (HRPs) are :histatin1; histatin2; histatin3; histatin5
They exert broad spectrum antibacterial ;antifungal; antiviral properties.
MOA is similar to Defensins. It also binds and complex Cu+2,Ni+2 ions leading to elimination of metal
ions and consequent inhibition of enzy.; their cofactors and microbial growth.
Histatins (esp.5) exert efficient activities against fungi; mainly C albicans. It inhibits a trypsin like
protease of Bacteroides gingi valis.
Histatins (esp.1) are incorporated into acquired pellicle on tooth surfaces and may play role in bacterial
colonization on tooth surfaces.
Histatin1 was shown to competitively inhibit absorption of HMWGP-binding cariogenic
bacteria(i.e,S.mutans onto tooth surfaces).
Histatins (esp.1;2;3)were identified as highly imp. for Wound closure stimulating factors of human saliva.
15. LACTOFERRIN
It is an iron- binding cationic glycoprotein present in most exocrine secretions,including saliva.
Major sources in saliva are sal. glands neutrophhil granulocytes entering oral cavity,mucosal epi.cells,GCF.
It is active against bacteria,fungi,parasites,viruses.MOA is similar to cationic peptides.
Besides,its cationic peptide activity,lactoferrin is a known scavenger of Fe+3 ions.It binds and sequestrates iron;
depriving micro.of iron i.e, essential for their growth.
It binds bacterial fimbrial adhesins;inhibiting epi.adhesions of certain bacteria.
Antiviral activity is due to binding and blocking of certain host cell GAGS used by viruses for adsorption,may
neutralise viruses by direct binding.
Immune modulatory and anticancer activity of lactoferrin seems likely.
ADRENOMEDULLIN:
A pluripotent hormone like cationic peptide of 52 AA.
Present in GCF;glandular saliva, whole saliva,oral epithelial cells excrete adernomedullin into saliva.
It is able to prevent bacterial growth (S.aureus) via generation of abnormal septum formation during cell
division.
16. CATHELICIDINS(LL-37)
Human Cathelicidin is referred to as hCAP-18 and most important derivative referred as LL-37,(an α-
helix type cationic antimicrobial peptide).
These are characterized by a conserved N-terminal domain that is proteolytically cleaved to generate the
active peptide.
Salivary LL-37 is likely to originate primarily from neutrophil leukocytes, is present in GCF.
MOA is similar to other cationic peptides .
It binds and neutralises bacterial LPS.
LL-37 and its derivatives are likely to play a role in re-epithelization of wounds and ulcers in oral cavity.
Exert immune activator and immune modular properties.
Secretory Leukocyte Proteinase Inhibitor (SLPI)
It is 107 aa serine protease inhibiters , controls excessive proteolysis caused by proteases of neutrophil granulocytes.
Hence, referred as antileukoprotease(ALP).
SLPI present in saliva is produced by keratinocytes of oral mucosa; neutrophil granulocytes entering oral cavity.
It is a non-glycosylated ,basic,single-chain,cysteine rich cationic polypeptide.
Being cationic in character, it acts as a cationic peptide. It exerts antimicrobial activity against both
bacteria(P.aeruginosa,S.aureus) and fungi(C.albicans), exerts antiviral properties .
17. DEFENSE PROTEINS OF SALIVA
Statherin
It is a tyrosine-glutamine and proline rich phosphoprotein .
It prevents precipitation crystallization of supersaturated calcium phosphate in ductal saliva and oral fluid.
It binds hydroxypatite ,indicating a possible role in acquired pellicle and dental plague formation .
It competitively inhibits absorption of HMWGPs to tooth surfaces and may inhibit adhesion of HMWGP-
binding cariogenic bacteria including S.mutans.
Besides antibacterial properties, it induces transition of hyphae to yeast in C.albicans , indicating its
contribution to oral defense against fungi.
Salivary Agglutins(SAG, gp 340)
SAG is a scavenger receptor cysteine-rich gp.
It acts as a pattern recognition scavenger receptor and as such it binds a broad range of oral pathogens,
including bacteria and viruses.
Also binds salivary proteins, including IgA and mucin MUC5b.
Based on premised properties , SAG efficiently aggregates bacteria and viruses, significatly increases their
clearance from mouth towards the stomach, leading to yheir acidic digestion.
18. LYSOZYMES
Salivary lysozyme is produced by salivary glands(highest level in sublingual saliva , by neutrophil granulocytes entering
mouth) ; also present in GCF.
It exerts muramidaze activity via hydrolysis of B-1,4 , glycosidic bonds between N-acetylmuramic acid and N-acetyl-D-
glucosamine of bacterial cell wall peptidoglycan
It mainly kills gram +ve bacteria that damages surface exposed peptidoglycan.
Killing of bacteria by lysozyme is , in many cases, largely independent of its enzymatic activity. In these cases, membrane
permeabillzing property of lysozyme seems to be active against both gram +ve and gram-ve bacteria ; fungi.
It exerts antiviral properties , may induce lysis of tumor cells.
It binds bacterial LPS , a bacterial surface structure and bacterial toxin, frequently responsible for tissue destructive
inflammatory reactions .
It can influence human granulocyte and lymphocyte function, may inactive viruses.
BPI, BPI-like and PLUNC proteins
These proteins belong to lipid binding protein family.
Primary sources of salivary BPI are neutrophil granolocytes; epithelial cells of oral
mucosa.
BPI exerts bactericidial, endotoxin neutralizing and opsonic properties.
PLUNC proteins appear to bind bacterial LPS similar to BPI, they do not exert direct killing activity, are
bacteriostatic similar to PSP.
Promotes agglutination of bacteria and modulate cytokine production.
The most important represantative of BPI-like proteins in saliva is PSP(parotid secretory protein). It is secreted
by salivary glands keratinocytes of oral mucosa.
19. PSP is bacteriostatic, bind bacterial LPS and promote agglutination of bacteria.
Salivary PLUNC proteins are primarily produced by major an dminor salivary glands.
There are 8 functional PLUNC in humans divided into 2 subgroups :-
a) Short-type S-PLUNC proteins :- (SPLUNC-1, SPLUNC-2, SPLUNC-3)
b) Long-type-PLUNC proteins :- (LPLUNC-7, LPLUNC-2, LPLUNC-3, LPLUNC-4, LPLUNC-6)
CYSTATINs
Human cystatin gene family contain 14 genes from which 7 cystatins are present in saliva namely:-
Cystatin-A, Cystatin-B, Cystatin-C, Cystatin-D, Cystatin-S, Cystatin-SA, Cystatin-SN.
Highest concentration found in submandibular saliva but present in parotid saliva at a lower concentration
is present in GCF.
They are cysteine protease inhibitors, blocking the action of endogenous, bacterial and parasitic protozoan
protease.
Cystatin-C and Cystatin-S inhibits bacterial growth (P.gingivalis)
Cystatin SN and Cystatin S are present in human acquired enamel pellicle, binds bacteria and bacterial
LPS.
Expert direct immonomodulatory properties, exert certain antiviral effect.
Both the peroxidase catalyze the oxidation of thiocyanat CSCN- by hydrogen peroxide, leading to
production of a much more bactericidial & fungicidal agent, namely hypothiocyanite (OSCN-)
Function of salivary peroxidare seems to be facilitated by DUOX-2, a homologue of catalytic core (gp21)
of NADPH oxidases.
20. α- Amylase
Salivary amylase is a highly abundant protein in saliva. Highest conc. was found in saliva of parotid
and palatine minor salivary glands.
Most widely known function-endoglicosidase activity. Splitting the α-1,4-glicosidic bindings of
several glycans, such as starch (amylopectin), amylase produces oligosaccharides (dextrin)
disaccharides (maltose, isomaltose) and monosaccharide glucose . Besides its enzymatic activity, it
also takes part in acquired pellicle formation on tooth surface .
It also performs a direct inhibitory effect on the growth of certain bacteria. It binds bacterial LPS .
Also exert virus inhibitory properties.
21. PROLINE RICH PROTEINS(PRPS)
PRPs form a major portion of salivary proteins(20-30% of total).
They are highly phosphorylated proteins. Major source are salivary glands, highest
concentration in parotid saliva.
Acidic PRPs contain a longer and highly acidic N-terminal region and somewhat different
repeat sequence, compared with basic PRPs.
Acidic PRPs binds bacteria, basic PRPs bind fungi whereas glycosylated PRPs bind bacteria
and viruses.
22. ROLE OF PRPS IN ENAMEL PELLICLE FORMATION
Acquired enamel pellicle is 0.1-1.0 µm thick layer of macromolecular material on the
dental mineral surface
Pellicle is formed by selective adsorption of hydroxyapatite-reactive salivary
proteins, serum proteins and microbial products such as glucans and glucosyl-
transferase
Pellicle acts as a diffusion barrier, slowing both attacks by bacterial acids and loss
of dissolved calcium and phosphate ions
REMINERALIZATION OF ENAMEL AND CALCIUM PHOSPHATE INHIBITORS
Early caries are repaired despite presence of mineralization inhibitors in
saliva
Sound surface layer of early carious lesion forms impermeable barrier to
diffusion of high mol.wt. inhibitors.
Still permeable to calcium and phosphate ions
Inhibitors may encourage mineralization by preventing crystal growth on
the surface of lesion by keeping pores open
23. CALCULUS FORMATION AND CALCIUM PHOSPHATE INHIBITORS
Calculus forms in plaque despite inhibitory action of statherin and PRPs in
saliva
May be due to failure to diffuse into calcifying plaque
Proteolytic enzymes of oral bacteria or lysed leukocytes may destroy
inhibitory proteins
Plaque bacteria may produce their own inhibitors
CALCIUM PHOSPHATE PRECIPITATION INHIBITORS AND PLAQUE
Statherin and PRPs might be expected to occur in plaque, have not been
detected
Plaque bacteria produce calcium phosphate inhibitors
Might be necessary to prevent calcification of bacteria -- happens with dead
cells
Immobilized crystal growth inhibitors can function as nucleators of crystal
growth
Immobilization may occur in plaque, encouraging calculus formation
24. Lack precise folded structure of globular proteins
Asymmetrical molecules with open, randomly organized structure
Polypeptide backbone (apomucin) with CHO side-chains
Side-chains may end in negatively charged groups, such as sialic acid and bound sulfate
Hydrophillic, entraining water (resists dehydration)
Unique rheological properties (e.g., high elasticity, adhesiveness, and low solubility)
Two major mucins (MG1 and MG2)
Functions
MUCINS
Tissue Coating
Protective coating about hard and soft tissues
Primary role in formation of acquired pellicle
Concentrates anti-microbial molecules at mucosal interface
Lubrication
Align themselves with direction of flow (characteristic of asymmetric molecules)
Increases lubricating qualities (film strength)
Film strength determines how effectively opposed moving surfaces are kept
apart
25. Aggregation of bacterial cells
Bacterial adhere to mucins may result in surface attachment, or
Mucin-coated bacteria may be unable to attach to surface
Bacterial adhesion
Mucin oligosaccharides mimic those on mucosal cell surface
React with bacterial adhesins, thereby blocking them
Lingual Lipase
• Secreted by von Ebner’s glands of tongue
• Involved in first phase of fat digestion
• Hydrolyzes medium- to long-chain triglycerides
• Important in digestion of milk fat in new-born
• Unlike other mammalian lipases, it is highly hydrophobic and readily enters
fat globules
26. CONCLUSION
Whole saliva is a major determinant of the environment on all the oral surfaces.
It plays an imp.role in physico-chemical as well as immune defense of
o.mucosal surfaces .Saliva plays an imp.role in fine regulation of o.mucosal
immune reactions ,as well as in healing of several mucosal lesions,wounds and
ulcers.
There are numerous defense proteins in saliva, some such as salivary
Igs&HSP70/HSPAs are involved in both innate and acquired immune
activation,whereas cationic peptides& other sal.defense proteins are primarliy
responsible for innate immunity.