Fig. 5: L. reuteri ZJ617 alters the metabolic profile of HFD-fed mice and increases the production of spermidine.

a OPLS-DA score plot for discriminating the metabolic profile of the LFD, HFD, and HFD + ZJ617. b Heatmaps showing the differential metabolites between HFD and HFD + ZJ617. c The metabolic pathways in HFD versus HFD + ZJ617. d Fold change of metabolite levels in the polyamine pathway in intestinal contents from mice treated with L. reuteri ZJ617 versus the control HFD (n = 9 per group). L. reuteri ZJ617 was independently cultured three times, and the (e) S-adenosylmethionine level in both the culture broth and cells were measured (n = 3 per group). f Study design of in vitro gastrointestinal tract simulation. The figure was created in BioRender. Ma, Y. (2024) https://BioRender.com/n79v306. The feces were collected from six adult volunteers with obesity (BMI ≥28). The fecal slurry was prepared and initially stabilized for 7 days, followed by 6 days of continuous fermentation during which L. reuteri ZJ617 or S-adenosylmethionine (SAM) was added daily. Each sample was collected from three independent fermentation waste extractions. g S-adenosylmethionine levels in fermentation broth. h Spermidine levels in the fermentation broth. Data were shown as mean ± SD. Significance is calculated based on two-tailed t-tests, with the exception of b calculated based on two-tailed Wilcox tests, c calculated based on a two-tailed hypergeometric test. Source data are provided as a Source Data file.