Paper - Review

DOI: 10.1186/s40168-021-01056-3

Abstract

Background

❗: 1⃣ localized aggressive periodontitis 2⃣ generalized aggressive periodontitis 3⃣ chronic periodontitis → are microbially driven diseases
❓: our inability → to separate disease-specific associations
← from those common to all three forms of periodontitis
→ has hampered biomarker discovery

‼: aimed → to map 1⃣ the genomic content 2⃣ the biological pathways
← the microbiome ← associated with these clinical phenotypes

∴ Estimated the extend
→ to which these biomes are governed ← by Anna Karenina principle
→ which states that eubiotic communities are similar ← between individuals
→ while disease-associated communities → are highly individualized

Methods

Collected
→ 1⃣ subgingival plaque ← from 25 periodontally healthy individuals
→ 2⃣ disease sites of 59 subjects ← with stage 3 peridontitis

Used shotgun metagenomics
→ to characterized the aggregate of bacterial genes

Results

❗: AKP was most evident in CP
← followed by GAP & LAP
∵ beta-disperison metrics

Discovered broad dysbiotic signatures
← spanning the three phenotypes
← with over-representation of pathways
→ facilitate life in 1⃣ an oxygen-poor 2⃣ protein-rich 2⃣ heme-rich 4⃣ pro-oxidant environment
→ enhance capacity → for 1⃣ attachment 2⃣ bioflim formation

❗: Phenotype-specific indicators → were more readily evident
← in LAP microbiome

❗: genes
← enable 1⃣ acetate-scavenging lifestyle 2⃣ utilization of alternative nutritional sources 3⃣ oxidate & nitrosative stress responses 4⃣ siderophore production
→ were unique to LAP

❗: An attenuation
← of 1⃣ virulence-related functionalities 2⃣ stress response
← from LAP to GAP to CP
→ was apparent

❗: Clinical phenotype of disease
→ resolved variance ← in the microbiome ← with greater clarity
← than the newly established grading system

❗: 1/3 of the metagenome of LAP → is unique → to this phenotype
← GAP shares significant 1⃣ functional 2⃣ taxonomic features ← with both 1⃣ LAP 2⃣ CP
∴ 1⃣ attenuation of an aggressive disease 2⃣ an early-onset chronic disease

Conclusion

❗: The distinctive features of the microbiomes
← associated with 1⃣ LAP 2⃣ CP
∴ these are discrete disease entities
∴ ❓: GAP is 1⃣ a separate disease 2⃣ an artifact ← induced by cross-sectional study designs

❓: Further studies
← on phenotype-specific microbial genes
→ are warranted → to explicate their role ← in disease etiology

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