Table 2.
Modification of the gut microbiome in preclinical and clinical investigations using various microbiota therapies.
| S.no. | Interventions | Models/Subjects | Major findings | Reference |
|---|---|---|---|---|
| Probiotic administration | ||||
| Human studies | ||||
| 1. | DW2009: a mixture of fermented soybean powder and L. plantarum C29 freeze-dried powder | MCI patients | Enhanced cognitive performance, higher blood BDNF levels, and increased Lactobacilli abundance. | Hwang et al. (2019) |
| 2. | Bifidobacterium bifidum BGN4 and Bifidobacterium longum BORI | Randomized double-blind, multicenter clinical trial. >65 years old (63 healthy elders) | Increased levels of serum BDNF level, mental flexibility, and alleviation of stress. | Kim et al. (2021) |
| 3. | Multispecies probiotics (Lactobacillus, Lactococcus, and Bifidobacterium) | 60–93 years old (20 AD patients) | Increased levels of serum kynurenine concentrations, kynurenine to tryptophan ratios indicates activation of dendritic cells and macrophages. | Leblhuber et al. (2018) |
| Animal studies | ||||
| 4. | Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 Lactobacillus rhamnosus | Lipopolysaccharide-induced rats | Reduction of pro-inflammatory cytokines, reduction of apoptosis in the hippocampus, and enhanced memory (increased expression of BDNF). | Mohammadi et al. (2019a,b) |
| 5. | Lactobacillus rhamnosus (GG), Bifidobacterium animalis lactis (BB-12), and Lactobacillus acidophilus (LA-5) | MPTP-induced mice | Butyrate, through upregulating neurotrophic factors and suppressing the level of Mao B, inhibited the death of dopaminergic neurons. | Srivastav et al. (2019) |
| 6. | Lactobacillus plantarum C29-fermented defatted soybean (FDS, DW2009) | 5XFAD transgenic mice | Suppression of Aβ, β/γ-secretases, caspase-3 expression, and NF-κB activation increased BDNF expression in the brain. | Lee et al. (2018) |
| 7. | Lactobacillus fermentum NS9 | Ampicillin-induced SD rats | GM proportion returned to normal, and deficits in spatial memory and anxious behavior caused by ampicillin were reversed. | Wang X. L. et al. (2015) |
| 8. | Bifidobacterium breve strain A1 | Aβ-injected male ddY mice | Increased cognitive function, controlled immunological responses, and decreased brain inflammation. | Kobayashi et al. (2017) |
| 9. | Lactobacillus plantarum MTCC1325 | D-galactose-induced AD albino rats | Enhanced histopathological in brain regions, acetylcholine levels decreased Aβ plaque formation, and increased cognitive function. | Nimgampalle and Kuna (2017) |
| 10. | Bifidobacterium breve CCFM1025 | AD mouse model | Enhanced synaptic plasticity, elevated levels of BDNF, fibronectin type III domain-containing protein 5 (FNDC5), and postsynaptic density protein 95 (PSD-95). | Zhu et al. (2021) |
| 11. | ProBiotic-4 (Bifidobacterium and Lactobacillus) | Aged Senescence-accelerated mouse prone 8 (SAMP8) mice | Decreased levels of IL-6 and TNF-α, Decreased LPS, TLR-4, and NF-κB, abrogation of retinoic-acid-inducible gene-I multimerization. | Yang et al. (2020) |
| 12 | Human-origin probiotic cocktail (five Lactobacillus and five Enterococcus) | C57BL/6 J male mice | Decreased inflammation, leaky gut, gut dysbiosis, and metabolic disorders. | Ahmadi et al. (2020) |
| Fecal microbiota transplantation (FMT) | ||||
| Animal studies | ||||
| 13. | ADLPAPT mice were administrated fresh feces of wild-type mice | (ADLPAPT) transgenic mouse model of AD | Amelioration of formation of Aβ plaques and neurofibrillary tangles, glial activation and cognitive dysfunction, decreased expression of genes associated with intestinal macrophage activity and inflammatory blood monocytes. | Kim et al. (2020) |
| 14. | Tg + FMT administrated were administered feces from WT mouse pellets. | APPswe/PS1dE9 transgenic (Tg) mice and wild-type mice | Decreased levels of Aβ40 and Aβ42, tau protein phosphorylation, decreased levels of COX-2 and CD11b, Increased synaptic plasticity (evident from synapsin I postsynaptic density protein 95 (PSD-95) and expression). | Sun et al. (2019) |