Probiotics Ameliorate Aging-Related Cognitive Impairments and Pathological Changes through Alleviating Telomere Attrition and Enhancing Mitochondrial Function in Senescence-Accelerated Mouse Prone 8 Mice

Aging-related cognitive impairment, characterized by DNA damage and mitochondrial dysfunction, still lacks effective treatment strategies. Recent findings suggest that <i>Lactobacillus delbrueckii</i> (LD), <i>Streptococcus thermophilus</i> (ST) and <i>Bifidobacterium longum</i> (LB) may have the ability to ameliorate mitochondrial dysfunction and DNA damage. Therefore, to elucidate the antiaging effects of these probiotics, we administered LD, ST, LB, and their combinations to 4 month-old senescence-accelerated-mouse-prone 8 (SAMP8) mice for 24 weeks. Consequently, these probiotics and their combinations alleviated neuronal damage, enhanced synaptic plasticity, mitigated telomere attrition, improved mitochondrial function, and enhanced cognitive and memory functions in aging SAMP8 mice. In the gut microbiota and metabolites, the relative abundance of <i>Limosilactobacillus</i>, <i>Ligilactobacillus</i>, piperidine-4-carboxamide, and Leu-Ile-Glu-Glu increased and that of <i>Paramuribaculum</i> decreased in the probiotic-treated SAMP8 mice. In summary, the antiaging effects, attributed to alleviating telomere attrition and enhancing mitochondrial function, for probiotics were confirmed in aging mice, with the probiotic combinations exhibiting a larger effect.