Human Stool Metabolome Differs upon 24 h Blood Pressure Levels and Blood Pressure Dipping Status: A Prospective Longitudinal Study

: Dysbiosis of gut microbiota (GM) has been involved in the pathophysiology of arterial
hypertension (HT), via a putative role of short chain fatty acids (SCFAs). Its role in the circadian
regulation of blood pressure (BP), also called “the dipping profile”, has been poorly investigated.
Sixteen male volunteers and 10 female partners were subjected to 24 h ambulatory BP monitoring
and were categorized in normotensive (NT) versus HT, as well as in dippers versus non-dippers.
Nuclear magnetic resonance (NMR)-based metabolomics was performed on stool samples. A 5-year
comparative follow-up of BP profiles and stool metabolomes was done in men. Significant correlations between stool metabolome and 24 h mean BP levels were found in both male and female cohorts
and in the entire cohort (R2 = 0.72, R2 = 0.79, and R2 = 0.45, respectively). Multivariate analysis
discriminated dippers versus non-dippers in both male and female cohorts and in the entire cohort
(Q2 = 0.87, Q2 = 0.98, and Q2 = 0.68, respectively). Fecal amounts of acetate, propionate, and butyrate
were higher in HT versus NT patients (p = 0.027; p = 0.015 and p = 0.015, respectively), as well
as in non-dippers versus dippers (p = 0.027, p = 0.038, and p = 0.036, respectively) in the entire
cohort. SCFA levels were significantly different in patients changing of dipping status over the
5-year follow-up. In conclusion, stool metabolome changes upon global and circadian BP profiles in
both genders