Thiamine status in humans and content of phosphorylated thiamine derivatives in biopsies and cultured cells.
BACKGROUND
Thiamine (vitamin B1) is an essential molecule for all life forms because thiamine diphosphate (ThDP) is an indispensable cofactor for oxidative energy metabolism. The less abundant thiamine monophosphate (ThMP), thiamine triphosphate (ThTP) and adenosine thiamine triphosphate (AThTP), present in many organisms, may have still unidentified physiological functions. Diseases linked to thiamine deficiency (polyneuritis, Wernicke-Korsakoff syndrome) remain frequent among alcohol abusers and other risk populations. This is the first comprehensive study on the distribution of thiamine derivatives in human biopsies, body fluids and cell lines.


RESULTS
Thiamine derivatives were determined by HPLC. In human tissues, the total thiamine content is lower than in other animal species. ThDP is the major thiamine compound and tissue levels decrease at high age. In semen, ThDP content correlates with the concentration of spermatozoa but not with their motility. The proportion of ThTP is higher in humans than in rodents, probably because of a lower 25-kDa ThTPase activity. The expression and activity of this enzyme seems to correlate with the degree of cell differentiation. ThTP was present in nearly all brain and muscle samples and in ∼60% of other tissue samples, in particular fetal tissue and cultured cells. A low ([ThTP]+[ThMP])/([Thiamine]+[ThMP]) ratio was found in cardiovascular tissues of patients with cardiac insufficiency. AThTP was detected only sporadically in adult tissues but was found more consistently in fetal tissues and cell lines.


CONCLUSIONS
The high sensitivity of humans to thiamine deficiency is probably linked to low circulating thiamine concentrations and low ThDP tissue contents. ThTP levels are relatively high in many human tissues, as a result of low expression of the 25-kDa ThTPase. Another novel finding is the presence of ThTP and AThTP in poorly differentiated fast-growing cells, suggesting a hitherto unsuspected link between these compounds and cell division or differentiation.
GIGA-Neurosciences, University of Liège, Liège, Belgium.
Marjorie
M
Gangolf
Jan
J
Czerniecki
Marc
M
Radermecker
Olivier
O
Detry
Michelle
M
Nisolle
Caroline
C
Jouan
Didier
D
Martin
Frédéric
F
Chantraine
Bernard
B
Lakaye
Pierre
P
Wins
Thierry
T
Grisar
Lucien
L
Bettendorff
D000818:Animals; D001706:Biopsy; D001826:Body Fluids / Q000378:metabolism*; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D051379:Mice; D010084:Oxidation-Reduction; D010766:Phosphorylation; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013831:Thiamine / Q000378:metabolism*
D013831:Thiamine