Abstract from Nigel Manning : B2 responsiveness in a TMAU patient

Abstract from Nigel Manning : B2 responsiveness in a TMAU patient

This is an abstract paper (pre-publication) done by Nigel Manning, Principal Clinical Scientist, Dept of Clinical Chemistry, Sheffield Children's Hospital, and others at the same hospital.

It is a case study of a patient with homocystinuria who was on betaine therapy and then over around 10 years started to have a 'fish odor' complaint. The patient was found to have the 158-308 DNA combo that can cause mild genetic deficiency of FMO3 enzyme. The urine sample had very high levels of TMA (392 mmols/mol).

It was decided to try B2 therapy and the TMA levels were checked 5 times over 240 days. In the graph, it can be seen the TMA levels dropped dramatically, eventually being 17 mmols/mol. This is still above Sheffield's normal saturation level of 10.8, but a vast improvement. Also, the % of TMA converted to TMAO  went from 7% to 83%, but this could be due to reducing the level of TMA-producing bacteria alone.

Presumably this study was carried out because people with homocystinuria have to take high doses of betaine. Betaine is known to cause high levels of dimethylglycine, which is recorded as causing a fish odor.

The TMA levels dropped, but we are told the TMAO levels did not conversely increase, rather, the overall TMA + TMAO level dropped. So it cannot be ruled out that the gut infection was reduced rather than B2 causing increase in TMAO function ?? Since high betaine levels are used for another disorder in this study, this suggests perhaps FMO3 function was increased. There still remains a few questions about B2 responsiveness that need to be checked.

All the same, it is an interesting study and B2 responsiveness would make a great study for TMAU. In this study, they used 100mg B2 twice a day.