A mixture of Postbiotics/Tyndallized Probiotics reduce Trimethylamine (TMA) in Trimethylaminuria models: Evidence from In Vitro and in Vivo Studies

Giuseppe Giannini^1*Sara Soldi²Marina Elli²Valeria Sagheddu²Andrea Castagnetti³Elisa Viciani³Laura Salvini⁴Gianfranco Battistuzzi¹Ferdinando Maria Milazzo¹Simona Alibrandi^5*Antonina Sidoti⁶

• ¹Alfasigma SpA, Bologna, Emilia-Romagna, Italy
• ²Advanced Analytical Technologies Srl, Fiorenzuola d'Arda (Piacenza), Italy
• ³Wellmicro srl, Bologna, Emilia-Romagna, Italy
• ⁴Toscana Life Sciences, Siena, Tuscany, Italy
• ⁵Department of Biomedical, Dental and Morphological and Functional Imaging Sciences, University of Messina, Messina, Italy
• ⁶Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy

Introduction: Trimethylaminuria, TMAU or "fish-odour syndrome", is a rare metabolic disorder characterized by a body malodour which smells like a decaying fish. This syndrome is caused by a FMO3 liver enzyme malfunction, leading to TMA accumulation. To date there is no definitive therapeutic treatment but only palliative care such as a controlled diet, taking antibiotics, or using acidic soaps to capture sweat-released Trimethylamine (TMA). Methods: Here we describe an innovative approach for the treatment of this disorder, the use of postbiotics/ tyndallized probiotics able to effectively inhibit the bacterial TMA lyase present, thus preventing the TMA formation. We have obtained a preparation (mixture of tyndallized probiotics and their postbiotics), derived from the L. paracasei fermentation in presence of garlic extract and senna leaf. This preparation was used in in vitro assays on human faecal slurry monitoring the levels of TMA released over time, and in vivo tests, in both Mus Musculus C57BL/6 (FMO3+/+) strain WT and C57BL/6-Fmo3em1Smoc(KO) mouse models, to measure the TMAO and TMA levels in blood and urine, along with gut microbiota analysis in faeces via Next Generation Sequencing (NGS). Results: L. paracasei fermentation yielded 4.1×10¹² CFU/g lyophilized powder. In vitro assays involving fecal slurries supplemented with the fermentation product demonstrated a reduction in trimethylamine (TMA) levels and the NGS analysis revealed that Collinsella, Clostridium and Streptococcus were the most bacterial genera TMA producer. The in vivo study showed a significant reduction in TMAO levels in C57BL/6(FMO3+/+) strain WT mouse models and in TMA levels in C57BL/6-Fmo3em1Smoc (KO) mouse. In addition, bacteria belonging to the TMA-producing genera were still present after treatment with the tested compounds, excluding their bactericidal action. The postbiotics obtained may find a useful therapeutic application both in prevention of cardiovascular events, and as valid supports to reduce the trimethylamine production, in trimethylaminuria patients.