Table 2.
Summary of the findings on the association of aging with changes in microbiomes from the different body sites
| Body sites | Predominant phyla | Cohort location | Recruited subjects number (age range) | Sequencing stage | α Diversity (taxonomic) | β Diversity (taxonomic) | Aging-related enrichment taxa | Aging-related decreased taxa | Reference | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Young | Elderly | Longevity | Shannon index | Richness | variation among individuals | ||||||||
| Gut | Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria | Sardinia (Italy) | 19 (21–33) | 23 (68–88) | 19 (99–107) | Illumina Hiseq and Miseq | Shotgun metagenomic sequencing and 16S rRNA V3V4 | ≈ | ≈ | ↑ | Methanobrevibacter smithii, Bifidobacterium adolescentis | Faecalibacterium prausnitzii, Eubacterium rectale | [145] |
| Firmicutes, Bacteroidetes | Bologna (Italy) | 20 (25–40) | 43 (59–78) | 21 (99–104) | Phylogentic microarry and qPCR | 16S rRNA | ↓ | ↓ | Anaerotruncus, Oscillospira, Christensenellaceae, Eggerthella | Faecalibacterium, Roseburia, Coprococcus | [146] | ||
| Skin | Actinobacteria | Sardinia (Italy) | 19 (21–33) | 23 (68–88) | 19 (99–107) | Illumina Hiseq and Miseq | Shotgun metagenomic sequencing and 16S rRNA V3V4 | Site-dependent alterations | ↑ | Staphylococcus, Streptococcus | Propionibacterium | [99] | |
| Actinobacteria | Shangai (China), urban and rural | 24 (25–35) | 22 (50–60) | 454 Pyrosequencing | 16S rRNA | ≈ | ↓ | [97] | |||||
| Actinobacteria | Japan | 18 (23–37) | 19 (60–76) | 454 Pyrosequencing | 16S rRNA | ↑ | ↑ | Corynebacterium, Acinetobacter | Propionibacterium, Staphylococcus | [98] | |||
| Mouth | Firmicutes (EN), Bacteroidetes (HC) | Osaka, Japan | 16 (79–94) | 15 (68–101) | Pyrosequencing | 16S | ↓ (EN) | Actinomyces, Streptococcus, Bacilli, Selenomonas, Veillonella, Haemophilus (increased in EN) | Prevotella, Leptotrichia, Campylobacter, and Fusobacterium (decreased in EN) | [71] | |||
| Cambridge, USA/São Paulo, Brazil | periodontis: young 152 (28.5 ± 4.7), middle 833 (35–64); periodontally healthy: young 119 (29.24 ± 6.2), middle 112 (35–64) | periodontitis 99 (69.6 ± 4.2); periodontally healthy 15 (67.8 ± 9.8) | Checkerboard DNA–DNA hybridization | Actinomyces (increase d in elderly with periodontal) | P. gingivalis and T. forsythia (increased in younger with periodontal) | [73] | |||||||
| Firmicutes | Danbury, CT, USA | 33 (70–82) | 32 (70–82) | illumina Miseq | 16S | ↑(healthy aging) | Streptococcus, Veillonella, and Rothia (NHA) | Neisseria, Haemophilus, Fusobacterium, and Capnocytophaga are enriched in healthy aging. | [72] | ||||
| Actinobacteria (in AMD) | Ontario, Canada | 5 (<59–89) | 13 (60>89) | Illumina NextSeq500 | 16S | Propionibacteriales, Rothia, Staphylococcus, and Cornyebacteriaceae (increased in AMD) | Fusobacterium and Bacilli (higher in controls) | [78] | |||||
| Nose | Ontario, Canada | 5 (<59–89) | 13 (60>89) | Illumina NextSeq500 | 16S | Actinomycetaceae, Gemella, Proteobacteria, Actinomyces, Veillonella, Burkholderiales (significantly higher in AMD) | Clostridia (increased in the control group) | [78] | |||||
| Lung (sputum) | Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria | Singapore | 24 (22–39) | 24 (60–71) | MiSeq Illumina | 16S | Not significant different | Not significant different | Not significant different | Firmicutes | Proteobacteria (Haemophilus, Lautropia) | [85] | |
| Bladder (urine) | Proteobacteria, Firmicutes | Zhejiang, China | 50 (50.06 ± 7.51) | 50 (71.86 ± 6.70) | MiSeq Illumina | 16S V3V4 | ↓ (Not significant) | ↓ (Not significant) | Peptococcus | Lactobacillus, Bifidobacteria | [134] | ||
| Firmicutes | UK | 23 (20–29) | 14 (50–59) | Eurofins Genomics | 16S | Not significant different | Not significant different | Mobiluncus | lactobacillus | [148] | |||
| Firmicutes, Proteobacteria | Bristol, UK | 13 (20–49) | 20 (50–70+) | 454 Pyrosequencing | 16SV1V3 | Not significant different | Not significant different | Jonquetella, Parvimonas, Proteiniphilum, and Saccharofermentans. | [152] | ||||
Vaginal ecosystem is not described in this table because the focus of studies concerning this ecosystem is never the aging per se, but the menopause and associated symptoms, therapies, or conditions