| Depression and anxiety | Maternal separation (MS) rat model | Chronically treated with Bifidobacteria | • Swim behavior ▼ and immobility ▲ in FST• Peripheral interleukin (IL)-6 release ▲• Noradrenaline (NA) ▼ in brain• Corticotrophin-releasing factor (CRF) mRNA level ▲ in amygdala | (Desbonnet et al., 2010) |
| Male Swiss mice | Orally treated with Lactiplantibacillus plantarum 286 over 30 days | • Open arm time ▲ in PM-DAT → Anxiolytic-like effect | (Barros-Santos et al., 2020) |
| IBS patients | Bifidobacterium longum NCC3001 | • Depression score ▼• Quality of life score ▲• Negative emotional stimuli ▼ in amygdala and fronto-limbic region | (Pinto-Sanchez et al., 2017) |
| Stress | Male C57BL/6 mice with chronic social defeat | Orally treated with Lacticaseibacillus rhamnosus JB-1 over 28 days | • Stress-induced anxiety-like behavior ▼• Social interaction with conspecifics ▲• IL-10+ regulatory T cells ▲ | (Bharwani et al., 2017) |
| ASD and ADHD | ASD mice model• Shank3B-/- model• VPA (valproic acid) model• MHFD (maternal high-fat diet) model• BTBR model | Treated with Limosilactobacillus reuteri over 4 weeks | • Sociability ▲ after treatment→ via the vagus nerve→ synaptic plasticity ▲ in oxytocin-dopamine reward system (VTA DA neuron) | (Sgritta et al., 2019) |
| Germ-free (GF) mice | Fecal microbiota transplantation of ADHD patients | • Anxiety behavior ▲ in OFT• Structural integrity of white and gray matter regions ▼ in internal capsule and hippocampus | (Tengeler et al., 2020) |
| Newborn infants | Treated with Lacticaseibacillus rhamnosus GG during the first 6 month | • At the age of 13 years, 17.1% diagnosis of ADHD or Asperger syndrome (AS) in the placebo and none in the probiotic group• Bifidobacterium species ▲ in feces during the first 6 month compared ADHD or AS diagnosis group | (Pärtty et al., 2015) |
| Alzhiemer’s disease (AD) | AD rat model | Lactobacillus acidophilus, Limosilactobacillus fermentum, Bifidobacterium lactis, Bifidobacterium longum | • Memory function ▲ in MWM test• Oxidative stress biomarker MDA(malondialdehyde) ▲ and SOD(superoxide dismutase) activity ▲ in hippocampus | (Athari Nik Azm et al., 2018) |
| AD rat model | Lactobacillus acidophilus, Bifidobacterium bifidum, Bifidobacterium longum | • Leaning function ▲ in MWM test• LTP ▲ and PPF ratio ▼ in hippocampus→ synaptic plasticity ▲ and presynaptic neurotransmitter release ▲ | (Rezaeiasl et al., 2019) |