Live Lactococcus lactis JCM 5805 and healthspan in C. elegans: a metabolic outsourcing study
In the abstract, live Lactococcus lactis JCM 5805 extended lifespan in C. elegans and raised L-citrulline and L-ornithine via bacterial arginine deiminase; heat-treated bacteria did neither. This is a worm study, not evidence of human lifespan benefit. [1]
Automatic summary · not editorially reviewed
The key findings
In the abstract, live Lc5805 consumption upregulated 74 cuticle-formation genes, mainly collagens, without activating host stress responses. [1]
Multi-omics and UPLC-MS analyses showed marked accumulation of L-citrulline and L-ornithine, attributed to high intestinal expression of bacterial arginine deiminase (arcA). [1]
Heat-treated Lc5805 failed to induce citrulline accumulation and lifespan extension, which the authors say confirms a need for active live bacteria. [1]
The source at a glance
- Study type / format
- Preclinical study in C. elegans (abstract)
- Population / context
- Caenorhabditis elegans worms, described as lacking a urea cycle
- Summary based on
- Study abstract
- Publication status
- Preprint · peer-review status not confirmed
- Original publication
- September 10, 2026
C. elegans without a urea cycle given live Lc5805
The abstract describes Caenorhabditis elegans, which it says lacks a urea cycle, and asks how Lactococcus lactis JCM 5805 (Lc5805) extends lifespan. Consuming live Lc5805 upregulated 74 cuticle-formation genes, mainly collagens, which the authors link to structural integrity for longevity without activating host stress responses. The design is a preclinical worm study; the abstract reports no sample sizes, follow-up times or effect sizes.
Supporting source [1]
Citrulline rise tied to bacterial arginine deiminase
Multi-omics and UPLC-MS analyses showed a marked accumulation of L-citrulline and L-ornithine, attributed to high intestinal expression of bacterial arginine deiminase (arcA). The authors call this “metabolic outsourcing”: the host uses bacterial metabolites and enzymes to support collagen maintenance and avoids its own energy expenditure. These are associations in worms; the abstract does not show that the same mechanism operates in humans.
Supporting source [1]
Heat-treated Lc5805 failed to extend lifespan
The abstract states that heat-treated Lc5805 did not induce citrulline accumulation or lifespan extension. The authors take this as confirmation that the system requires active metabolic and enzymatic activity by live bacteria in the gut. This comparison supports the role of live bacterial activity in the worm model, but it remains an abstract-level finding in C. elegans, not a demonstrated human healthspan effect.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. This is a preclinical C. elegans study, and the abstract reports no sample sizes, follow-up or effect sizes. Findings do not establish human lifespan or healthspan benefits.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Ito A, Kyoui D, Kawarai T, Matsufuji H, Suzuki C. · europepmc.org · September 10, 2026