[Influence of homeopathically processed coenzyme q10 on proliferation and redifferentiation of endothelial cells].

Background: Coenzyme Q10 (Co Q10) is vital for regulating cell metabolism and cell proliferation. The controlled proliferation of cells is prerequisite for the regeneration of tissues.

Aim: The aim of this study was to clarify whether homeopathically processed Co Q10 has an influence on the proliferation of freshly seeded endothelial cells, on the division rate of differentiated confluent endothelial cells, and on the redifferentiation of differentiated endothelial cells in vitro.

Methods: By the determination of cell numbers, the influence of Co Q10 on the proliferation of undifferentiated endothelial cells from the human umbilical vein was examined. For this assay different potencies of Co Q10 and freshly seeded endothelial cells were used. Prior to the proliferation assay the in vitro cytotoxic concentrations of Co Q10 were determined. The influence of Co Q10 on the division rate of differentiated confluent endothelial cells was determined by measuring the intake of the base analogue bromodeoxyuridine (BrdU). For the testing of differentiation, the expression of the von Willebrand factor (vWF) - the marker protein typical for endothelial cells - was observed while Co Q10 was present. A flow cytometric assay was used for the analyses.

Results: While only the D5 potency showed toxic effects, the other tested potencies of Co Q10 did not show any cytotoxicity. The potencies D7-D10 of Co Q10, especially the D8 potency, caused an increase in the proliferation of growing endothelial cells. By contrast, Co Q10 (D8) had no influence on the rate of incorporation of BrdU into confluent, contact-inhibited, and differentiated endothelial cells. In the case of confluent dedifferentiated cells incubated with Co Q10 (D8), no increase in the expression of the vWF was observed, either.

Conclusions: Homeopathically processed Co Q10 (D8) has a stimulating influence on the proliferation of growing cells in vitro. This confirms its function in the regulation of cell metabolism and cell proliferation. The stimulating influence, however, does not extend to the redifferentiation process. Co Q10 has no effect on the low division rate of subconfluent and of confluent, contact-inhibited, differentiated endothelial cells. Furthermore the expression of endothelial cell-specific differentiation antigens on dedifferentiated endothelial cells is not influenced by Co Q10.