Background: Investigation of the direct link between l-carnitine (LC), a quaternary ammonium compound that facilitates the passage of unsaturated fatty acids into the mitochondrial matrix, and free calcium (Ca2+) is needed to explain a number of varying results obtained from different in vitro and in vivo studies of LC as a supplement.
Methods: The chemical structure of LC, which contains oxygen ligand atoms, prompted to measure its activity as a Ca2+ chelator. The measurement was carried out spectrophotometrically by measuring the reduction in the formation of Ca2+-o-cresolphthalein complexone (Ca-CPC) in the presence of different doses of LC (0.075, 0.75, and 7.5 mM) compared to the control (0.0 mM LC).
Results: The effect of LC was measured as a free entity in solution and when added to human serum. Our results showed a significant decrease (p<0.05) in the average absorbance of Ca-CPC in the presence of LC compared to the control.
Conclusions: In conclusion, LC exhibits a significant Ca2+ chelating activity. As Ca2+ is vital in the biochemical and physiological processes of living cells, LC could be affecting the calcium-dependent biological systems by limiting the levels of free Ca2+. Examples include decelerating the blood clotting process, amplifying the effect of anticoagulants, reducing nitric oxide synthase activity, inhibiting platelet aggregation, and decreasing sperm motility.
This work is supported by both Jordan University of Science and Technology (grant number 20120135) and Cleveland State University.
Conflict of interest statement
Authors’ conflict of interest disclosure: The authors stated that there are no conflicts of interest regarding the publication of this article. Research funding played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.
Research funding: None declared.
Employment or leadership: None declared.
Honorarium: None declared.
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