Longevity in mice is promoted by probiotic-induced suppression of colonic senescence dependent on upregulation of gut bacterial polyamine production.
Level 5 - mechanism / opinion, no new human data
Animal research without human clinical data
PubMed 21858192 · doi:10.1371/journal.pone.0023652
What was done
Ten-month-old female Crj:CD-1 mice were fed a diet supplemented with the probiotic strain Bifidobacterium animalis subsp. lactis LKM512 for 11 months, while a control group received an unsupplemented diet. Survival was evaluated with Kaplan-Meier curves. Researchers measured fecal polyamine (PA) and short-chain fatty acid concentrations via HPLC, assessed intestinal bacterial groups via 16S rRNA gene expression, examined colonic mucosal integrity histologically, and analyzed colonic gene expression profiles using DNA microarrays and RT-qPCR.
What was found
LKM512-treated mice survived significantly longer than controls (P < 0.001) and developed fewer tumors and skin ulcers. Fecal polyamine levels were significantly increased in the probiotic group (P < 0.05), though short-chain fatty acids showed no difference. Treated mice exhibited enhanced mucus secretion, better maintenance of tight junctions, and downregulation of aging- and inflammation-associated genes, yielding gene expression patterns at 21 months resembling 10-month-old untreated mice. Specific numeric lifespan values and group sizes were not reported in the abstract.
Why it matters
This study outlines a potential gut-mediated mechanism for lifespan extension in mammals, linking probiotic-induced intestinal polyamine production to preserved mucosal barrier integrity and reduced chronic inflammation.
Limits
The investigation was conducted exclusively in female laboratory mice, precluding direct extrapolation to human longevity or males. The abstract lacks exact sample sizes, numerical values for median or maximum lifespan, and effect sizes for gene expression changes.
Cited by
- supports A Japanese research group published findings showing that specific gut bacteria overproducing polyamines reduce colon cancer development and aging.